Computer Studies KCSE Mock Exams and Answers {Latest Best Collections}

Maverick John

1 month ago

MOCKS 1 2023

COMPUTER STUDIES

PAPER 1 MARKING SCHEME

FORM FOUR

Answer ALL questions in the spaces provided

Differentiate between embedded computer and dedicated computer (2mks)

Embedded computers are special purpose computer used inside another device and usually dedicated to specific functions.
Dedicated computer is a general purpose computer designed to perform a specific task.

The current monitor technology use LED back lit technology. Give two advantages of using TFT monitors over CRT monitors (2mks)

Images formed in TFT do not suffer from angle distortion
TFT have low power consumption than CRT
TFT have a higher resolution than CRT

A Form four student wants to send a large document to a printer.
State the name for the area of memory that the document is sent to immediately from RAM (2mks)

Input buffer
As the printer runs out of paper during printing, the operating system sends a signal back to the computer to stop temporarily. Name this function of the operating system Interrupt handling (1mk)

a) Differentiate between a flash memory and compact disk as used in computer storage devices (2 mks)

Flash memory	Compact disk
ü Solid state device	ü Optical media
ü Plugs directly to the USB port	ü Requires a disk drive
ü Fast access of data	ü Slow access of data
ü Uses circuitry access	ü Has moveable read and write head

b) People like using a DVD over a compact disk yet they are of the same physical size, state three reasons that justifies this (3mks)

A DVD has a higher storage capacity
A DVD offers a better sound and picture quality than a CD

For a monitor to display images, it must be connected through video port to a video adapter or controller mounted on the mother board. What is the role of a video adapter (2mks)

It determines the resolution and clarity of the monitor

Name four categories of input devices (2mks)

Keying in devices
Pointing devices
Scanning devices
Automated method

Name any two physical measures taken to protect a computer lab from unauthorized access.(2mks)

Burglar proofing the room
Use of alarms
Use of padlocks
Use of special cards
Employing security guards

Most word processors have some automated features such as word wrap and type over modes. Describe these features (2mks)

A wordwrap is a feature that enables the cursor to move automatically to the start of a new line/page
Type over mode (overwrite mode) enables the user to edit an individual character of a word in a text document

Differentiate between proofreading and formatting a document as used in word processing (2mks)

Proofreading is the process of checking whether the document has typographical or grammatical errors
Formatting a document refers to enhancing the appearance of a document to be attractive and appealing to the eye of the reader

Most computerized systems in different organizations face a lot of unauthorized access such as Eavesdropping, Surveillance and Industrial espionage. State a control measure against each vice (3mks)

Eavesdropping: refers to tapping or listening into a communication channel to get information
Surveillance: Refers to monitoring use of computer system and networks using background programs such as spyware and cookies
Industrial espionage: it involves spying on competitor to get information that can be used to cripple the competitor

A world wide web is a vast virtual space in the internet where information is made available such as web portals and blogs. Different between a web portal and a blog (2mks)

Web portal: it is a specialized websites that offer restricted services such as e-learning, searching, e-mail, and sports to registered user updates, financial news and links to selected websites.
Blog: It is a website that contains personal information which can easily be updated

Differentiate between filtering and hiding of rows/columns as used spreadsheets(2mrks)

Filtering is the process of finding and working with a subset of related worksheet. This will display only the rows that meet the condition or criteria specified.
Hiding columns: its the process of making a column not be shown on the display or printed when you print the worksheet. The columnis not deleted.

Industrial plants use computer systems in different ways such as Computer Aided design, manufacturing, Simulation and process control. Explain how computers are used in the mentioned areas above (4mks)

Computer Aided design: it is an integrated system that allows products that have been designed using design application software
Simulation: it allows some activities that would otherwise be expensive and dangerous in real life to be put under test
Process control: it refers to the use of a computer system to control an ongoing physical process.

a) Differentiate between Job displacement and Job replacement (2mks)

Job replacement implies that the employees who are computer illiteratelose their jobs and replaced by computer literate people
Job displacement is where the computer illiterate workers are moved from a department with computers to another place which does not require computer literacy.

b) State three advantages of using automated production in manufacturing plants(3mks)

Increased efficiency due to the balancing of workload and production capacity
Improved customer service
Efficient utilization of resources such as raw materials

Due to high demand and dynamic nature of computers and information systems, there is need for qualified computer trainers are required. What are the roles of computer trainers(3mks)

Training people on how to use a computer and various application programs
Developing training reference materials
Guide learners on how to acquire knowledge through carrying out research
Advising the learners on the best career opportunities in the field of ICT
Preparing learners for ICT examinations

SECTION B.

Condition?

yes

statement

WHILE..DO Loop

Condition?

statements

Yes

REPEAT… UNTIL Loop

. a) By use of a Flowchartconstruct, differentiate between a while loop and Repeat… Until loop (4mks)

In the WHILE Loop, the condition is tested before the execution of statements while REPEAT loop statements are executed before the condition is tested
In WHILE loop, statements are executed until the condition becomes FALSE the you exit while in REPEAT loop, you exit when the statement is true
In WHILE loop,statementsmay exit without any statement being executed while in REPEAT loop atleast one execution of statements must be done

b)Angela deposits 3500 shillings in a microfinance company at an interest rate of 20% per annum.At the end of each year, the interest earned is added to the deposit and the new amount becomes

the deposit of that year.

Write an algorithm for a program that would track the growth of the deposits over a period of six years. (5mks)

Start

Input initial deposit

Input interest rate

Set deposit to initial deposit

Set year to 0

While year £ 6 Do

Interest = Deposit x Interest rate

Total = Deposit + interest

Deposit = Total

Year = Year + 1

END WHILE

Print, deposit, year

STOP

(b) Draw a flowchart for above algorithms. (7mks)

Start

Input Deposit

Input interest rate

Principal = initial deposit year = 0

Print deposit

Total = deposit + interest

Deposit = total

Year = year + 1

Interest = deposit X interest rate

Print year

Stop

Is year £

. a) Differentiate between a primary key and a foreign key as used in Database (2mks)

Primary key is a special index that enforces uniqueness in a table
Foreign key is a field in a table that matches the primary field in another table

b) State four factors to be considered when designing a good database (4mks)

Carefully study the requirements of the user in order to define all the data inputs, outputs and relationships required
Design a draft database on the paper to determine the number of files or tables required
Divided the information into separate fields, records and tables to allow flexibility in manipulating the database
Define a field for each table that will be used to identify each record uniquely
Give the most important fields the first priority
Design data entry forms needed for the database

c) Explain the use of each of the following field datatypes as used in database (3mks)
OLE object

It is used for storing graphical objects such as pictures

Look up wizard

It is a field displays the data as a drop down list so that the user can select the desired value from the list
Memo
It is a field in database that contain alphanumeric data and can accommodate a maximum of 32000 characters

d) kamau has been experiencing a lot of problems in his computer. As a result, he decided to format his computer and re-installed a new operating system.
What is Formatting in relation to the above context (2mks)

It is the process of preparing a new storage media by imprinting empty sectors and tracts on the surface of the disk so that the operating system can recognize and make it accessible

What precaution must kamau observe before formatting his computer (1mk)

Make a backup of all the documents to avoid losing them

e) You are required to purchase an operating system. State three factors that you should consider before acquiring the software (3mks)

Hardware configuration
The type of computer in terms of of size and make
The application software intended for the computer
User-friendliness
Documentation available
Cost of the operating system
Reliability and security provided by the operating system

18.Virtual reality –is a condition in which a person becomes psychologically immersed in an artificial setting generated by a computer system

b) Application areas of virtual reality

-represents any three dimensional real objects such as buildings, landscape

-represent any three dimensional abstract objects

-entertainment

-training of medics, military among others

-assistance to the physically challenged people in the society

c) Head gear–it is equipment made up of two tiny displays and sound systems. These help to direct images and sound from the source to the eyes or ears, enabling the wearer to look through the virtual setting

–Body suite–this is made up of conductor wires wound in a rubber suit. The wires sense the body movement and convey the data into the system which in turn changes the position of the user in the virtual world.

d) Artificial Intelligence–is a branch of computer science that is concerned with developing artifacts with the ability to perform the same kind of functions that characterize human thought and actions (award 1mk for correct definition)
e) Components of an experts system

User interface-display screen that enable the user to interact with the system
knowledge base- expert system’s data base of knowledge about a particular subject
inference engine- software that controls search for knowledge in the knowledgebase and produce conlusions.

a) Binary systems has been used to develop most electronic devices. Give three advantages of using binary (3mks)

It is difficult to develop devices that can understand or process natural languages directly it is easier to develop electrical circuits based on binary ON/OFF
All forms of data can be represented in binary system format
Binary devices are more reliable
They became smaller in size
They use less energy

b) Convert the following number systems (4mks)
625₁₀ to binary

Using long division get the binary of 37₁₀ =100101₂

get the binary of the decimal by multiplying repeatedly by two i.e 0.625₁₀=0.101₂

Add the binary of the whole number and the decimal

100101₂+0.101₂=100101.101₂

EF₁₆to Octal

HEXADECIMAL	B	C	D	E	F
BINARY	1011	1100	1101	1110	1111

Group In terms of three 101,111,001,101.111,011,110

To octal 5715.736₈

c) Using twos complement, perform the following arithmetic opration leaving your answer in decimal notation (4mks)

39₁₀ – 19₁₀

using long division get the binary of:

39₁₀= 100111₂

19₁₀= 10011₂

write the binary of 19₁₀ in 8-bits 19₁₀= 00010011₂

ones complement of the binary of 19₁₀=11101100

twos complement ones complement =11101101

add the binary of 39₁₀ to the twos complement of 19₁₀

11101101

+0100111

(1)00010100 ignore the overflow

(1×2⁴)+(1×2²)=20₁₀

d) one of the student in the Diocese was developing a file. List any four attributes that the student must consider in the development process (2mks)

e). downloading – is a process of transferring infor mation from a remote computer to a local storage.

Hyperlink– is a link infor m of text on a web page that causes onother web pages to open when the link is clicked.

Key field
The data type
The lenghth of each field
Back up and recovery strategies

a)(3mks)

To enable the analyst to test the system in phases
The operations and results of both systems are compare and evaluated
Errors can be identified and corrected before the old system is abandoned

b) State three reasons why an organization may change an information system(3mks)

New opportunities
Incase of problems in the current system
New directives

c) Different students were asked to state the characteristics of a system. The responses were as follows:
i) They are holistic
ii) They are open or closed systems

They have a boundary and environment.

Explain each of the above responses (3mks)

Holistic system: the different components of a system are grouped together to make a whole
Open or Closed: open system receives input from and gives out to the environment and can adopt to changes in the environment.
Boundary and Environment: it is a space within which the component operates.

e) Explain the following data collection stages as used in data processing (3mks)
i) Data preparation

It is the process of converting data from source documents to machine readable format

ii) Media conversion

This is where the data is converted from one medium to another

iii) Input validation

It is the process taken during data entry to prevent wrong data from being processed by subjecting to validity checks

f) State three ways a data entry clerk may use to reduce the threat to data integrity(3mks)

Back up data
Control access to data by enforcing security measures
Design user interfaces that minimizes chances of invalid data entry
Using error detection and correction software when transmitting data
Using devices that directly capture data from the source

NAME: ……………………………………. INDEX NUMBER: ………….………………….. SCHOOL……………………………. SIGNATURE: …………………DATE:……………….

451/1

COMPUTER STUDIES

PAPER 1

TIME: 2½ HOURS

MOCKS 1 2023

KENYA CERTIFICATE OF SECONDARY EDUCATION

COMPUTER STUDIES

PAPER I

INSTRUCTIONS TO CANDIDATES

Write your name and index number in the spaces provided.
This paper consist of two sections A and B.
Answer all questions in section A.
Answer question 16 (Compulsory) and any other THREE questions in section
All answers should to be written in the spaces provided in the question paper

For Official use only.

Section	Question	Max. Score	Candidates Score
A	1 – 15	40
B	16	15
	17	15
	18	15
	19	15
Total Score	20	15

This paper consists of 14 Printed pages.

Candidates should check the question paper to ensure that all the

Papers are printed as indicated and no questions are missing

SECTION A (40 MARKS)

Answer all the questions in this section

Differentiate between embedded computer and dedicated computer (2 marks)

The current monitor technology uses LED backlight technology. Give two advantages of using TFT monitors over CRT monitors (2 marks)

………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

A form four student wants to send a large document to a printer.

State the name for the area of memory that the document is sent to immediately from RAM (1 mark)

………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

As the printer runs out of paper during printing, the operating system sends a signal back to the computer to stop temporarily. Name this function of the operating system (1 mark)

a) Differentiate between a flash memory and a compact disk as used in computer storage devices (2 marks)

b) People like using DVDs over compact disks yet they are of the same physical size. State three reasons that justifies this (3 marks)

For a monitor to display images, it must be connected through video port to a video adapter or controller mounted on the motherboard. What is the role of a video adapter?

(2 marks)

Name four categories of input devices (2 marks)

State any two physical measures taken to protect a computer laboratory from unauthorized access (2 marks)

Most wordprocessors have some automated features such as word wrap and type over mo Describe these features (2 marks)

Differentiate between proofreading and formatting a document as used in wordprocessing (2 marks)

Most computerized systems in different organizations face a lot of unauthorized access such as Eavesdropping, surveillance and industrial espionage. State a control measure against each vice (3 marks)

A world wide web is a vast virtual space in the internet where information is made available such as webportal and blogs. Differentiate between a web portal and a blog.

(2 marks)

Differentiate between filtering and hiding of rows /columns as used in spreadsheets

(2 marks)

Industrial plants use computer system in different ways such as computer aided design, manufacturing simulation and process control, explain how computers are used in the mentioned areas above (4 marks)

a) Differentiate between job displacement and job replacement (2 marks)

State three advantages of using automated production in manufacturing plants

(3 marks)

Due to high demand and dynamic nature of computers and information systems, there is need for qualified computer trainers. What are the roles of computer trainers? (3 marks)

SECTION B (60 MARKS)

Answer question 16 (COMPULSORY) and any other THREE questions from this section

a) By use of a Flowchart, differentiate between a while loop and Repeat……..Until loop

(4 marks)

Angela deposits 3500 shillings in a microfinance company at an interest rate of 20% per annum.At the end of each year, the interest earned is added to the deposit and the new amount becomesthe deposit of that year.
Write an algorithm for a program that would track the growth of the deposits over a period of six years. (5mks)

(b) Draw a flowchart for above algorithms. (6mks)

a) Differentiate between a primarykey and a foreign key as used in database (2 marks)

b) State four factors to be considered when designing a good database (4 marks)

c) Explain the use of each of the following field datatypes as used in database (3 marks)
i) OLE object

ii) Lookup wizard

iii)Memo

d) Kamau has been experiencing a lot of problems in his computer. As a result, he decided to format his computerand re-installed a new operating system.
What is formatting in relation to the above context (2 marks)

What precaution must Kamau observe before formatting his computer (1 mark)

e) You are required to purchase an operating system. State three factors that you should consider before acquiring the software (3 marks)

(a) What is Virtual reality? (1 mark)

(b) Explain three application areas of virtual reality (3 marks)

………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

c). Explain the following interactive sensory equipment used in virtual reality. (2 marks)

Head gear.

Body suit.

(d) What is Artificial Intelligence? (1 mark)

e). State and explain three components of an experts system. (6 mark)

(d) Most computerized security systems make use of Biometric analysis, name two physical features of human beings that can be considered in this analysis.(2mks)

………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

a) Binary system has been used to develop most electronic devices. Give three advantages of using binary (3 marks)

b) Convert the following number systems (4 marks)
37.625₁₀ to binary

BCD.EF₁₆ TO octal

Using Two’s compliment, perform the following arithmetic operation leaving your answer in decimal.

39₁₀-19₁₀(4 marks)

One of the students in the Diocese was developing a file, list any four attributes that the student must consider in the development process (2 marks)

Define the following terms in relation to internet (2 marks)
i). Downloading

……………………………………………………………………………………………………………………………………………………………………………………

…………………………………………………………………………………………

ii). Hyperlink

a) A system analyst in Mukumu preferred using phased changeover to implement a new system. State three reasons for this preference (3marks)

b) State three reasons why an organization may change an information system (3marks)

c) Different students were asked to state the characteristics of a system. The responses were:
they are holistic
they are open or closed systems

they have a boundary and environment

Explain each of the following responses (3 marks)

Explain the following data collection stages as used in data processing (3 marks)
data preparation

………………………………………………………………………………………’……………………………………………………………………………………………………

media conversion

Input validation

State three ways a data entry clerk may use to reduce threats to data integrity

(3 marks)

………………………………………………………………………………………’……………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

………………………………………………………………………………………………

THIS IS THE LAST PAGE PRINTED

451/2

COMPUTER STUDIES

PAPER 2

FORM 4

TIME: 2½ HOURS

MOCKS 1 2023

KENYA CERTIFICATE OF SECONDARY EDUCATION

COMPUTER STUDIES

PAPER 2

INSTRUCTIONS TO CANDIDATES

Type your name and index number at the top right hand corner of each printout.
Write your name and index number on the CD provided
Write the name and version of the software used for each question on the answer sheet.
Passwords should not be used while saving in the CD
Answer all questions.
All questions carry equal Marks.
All answers must be saved in the CD
Make a printout of the answers on the answer sheets provided.
Hand in all the printouts and the CD

This paper consists of 4 printed pages.Candidates should check the question paper to ensure that all pages are printed as indicated and no questions are missing.

Question One

The following data is an extract of data obtained from Movers Transport company records. Study the data and answer the questions that follow.

AREA	PRODUCER ID	NAME	QUANTITY DELIVERED (KG)	TOTAL COST	TRANSPORT COST	GROSS COST	DEDUCTION	NET PROFIT
101B	115	Selina Mwao	4562
79A	145	Yvonne Kibet	1254
79A	012	Dorothy Namulungu	235
79A	561	Tiffany Wangui	8954
101B	016	Asha Waningu	9658
20Z	123	Ruth Mellanie	7895
20Z	458	Afif Mumtaz	456
101B	654	Pelah Wonder	421
20Z	758	Christabel Simbauni	7895

a) Enter the data shown above into a spreadsheet giving it an appropriate title, center and bold across the worksheet. Save the workbook as WORK01. Rename the worksheet as Jan records (10 Marks)
b) Copy the data to a new worksheet and add the details of producer Valence Masitsa of area 101B, ID 452 with quantity of produce of 2,700kg in an appropriate row. (1 Mark)
c) Insert double borders around every cell and every row. (2 Marks)
d) Use a function to calculate the Total cost for the producer with ID number 115 given that the price per KG of the produce is Sh.41 .00 (2 Marks)
e) Use the formula for Total cost obtained for producer Selina Mwao and use it to calculate the gross cost for all the farmers (2 Marks)
f) Use if function to calculate transport cost for all the producers given that transport is charged per Kg is as follows (5 Marks)

AREA	Price per kg
101B	5.00
20Z	3.50
79A	4.00

g) Insert the value 20% in cell E14. Using absolute cell referencing calculatedeductions, given that the deduction is 20% of the Total cost. (4 Marks)
h) Using a function calculate the Net cost, given that Net cost is Gross cost minus deductions and gross cost is Total cost plus Transport cost (4 Marks)
i) Format the columns containing currency values to currency with 2 decimal places and prefix Ksh. Rename the worksheet PRODUCE PAY. (3 Marks)
j) Arrange the records in ascending order of the producer ID. (2 Marks)
k) Copy the contents of worksheet Jan records to a new worksheet and rename it as Filtered. By applying suitable filter condition, display records for all producers except those from area 79A. (4 Marks)

1) Use subtotals function to calculate subtotals for the quantity delivered, gross pay and net pay from each area. (3 Marks)

m) Create an embedded pie chart showing the total quantity of produce delivered for each area .The chart should have the following details.
Chart title: Area Total produce delivered
Legend Position: Right

Save it as CHART 1 (5 Marks)

n) Print Jan records, Produce Pay and Filtered in landscape orientation. (3 Marks)

Question 2

You are part of a wedding committee of your friend and you have a vast knowledge of using a computer; you are tasked to be in charge of the wedding cards. Using a desktop publishing software, design the wedding card as it appears. Name the file as W-Card. (24marks)

Prepare the page layout specifications as follows:
Paper size: A4 portrait (2mks)
Grid guides (3mks)
Column guides: 1
Row guides: 2
Spacing: 3”
Margins guides (2mks)
Left and right: 24”
Top and bottom: 25”

Format the Outer heart shape in the middle part of the design to the following specifications: (4marks)
1. Color: Red
2. Outline: Light blue

Height:2.64”

Width: 2.84”

Perform the following formatting on the rectangle of the first part of the design.
1. Apply an outlineshadow. (1mark)
2. Background Texture fill – Newsprint. (2Marks)

Add a glow (Accent 1, 18pt glow), glow size 25pts, and 57% transparency. (4marks)

Change the paragraph text starting from “Request the blessings…” to color coldwith line spacing of 75sp. (2marks)
Format the names of the bride and bridegroom to have a strikethroughand a dotted underline. (2marks)
Group all objects in the design. (2marks)
Insert a page header “LOVE IS A GOOD THING”. (1mark)
Print the publication. (1mark)

a	Title , centre, bold, save rename	@2 each max 10 marks
b	Copy new worksheet add details
c	Double boarders	for each cell and row formatted max 2marks
d	Function (observe equal sign and product of cell with 41 by kgs ) =PRODUCT(d2:d11) =187042 Assuming 41 is entered in cell d11	2marks
e	Correct formula copied to all cells =(D2*D11)+G2	2 marks
f	Correct Function =if(A2=101B,D25, IF(A2=20Z, D23.5, IF(A2=79A, D2*4))) ASSUNG A STUDENT TYPED 101 B IN A2 THEY CAN USE THE CELL ADRESS AS WELL AS 5 IN CELL LETS SAY E12	5marks
g	Use of dollar sign in absolute e.g. =($E$14*$E$2$)	@2 each max 4
h	Function =SUM(E2:F2:-H2) Copy to other cells	3 marks 1 mark
i	Currency 2 decimal places Ksh Rename to PRODUCE PAY	1 mark 1 mark 1 mark
j	Arrange from smallest number to the largest (012-758)	2 marks
k	Copying to another worksheet Rename as filtered filter conditions Display excluding area 79A	1 mark 2 marks 2 marks
l	Check sort criteria by area code( since it’s the only column that will be used to isolate data) Check formula for subtotals	3 marks
m.i	Chart –with title: area total produce delivered	2 marks
ii	Legend position: right	1 mark
iii	Saved chart as CHART 1	2 marks
n	Print records-jan Produce pay Filtered landscape orientation	1 mark 1 mark 1 mark

PAPER 2 MARKING SCHEME

QUESTION 1

Designing and typing	Save as W-Card	2marks
	Design the heart	4 marks
	Fully typed text and bolded on the names	9 marks
	Word art	4 marks
	Text added and formatted in rectangles	3 marks
	Boarders	2 marks
a. i)	Paper size A4	2marks
ii	Gridlines –column guide: 1 -row guides :2 -spacing 0.3	@1 total 3marks
iii	Margin guides –left and right 0.24 – Top and bottom 0.25	@ total 2 marks
b	Format color red Outline light blue Height 2.64 Width 2.84	@ 1 total 4
c	Applying shadow Background texture fill-newsprint Add glow(accent 1, 18pt glow), glow size 25pts and 57% transparency	1 2 4
d	Color gold of specified paragraph Line spacing 0.75sp	1 1
e	Format by strike through dotted underline	1 1
f	Grouping all objects	2
g	Header	1
h	printing	1

QUESTION 2