describes the phases of various methodologies used to develop software.

1. Question one.
a) The systems development life cycle (SDLC), also referred to as the application
development life-cycle, is a term used in systems engineering, information systems and
software engineering to describe a process for planning, creating, testing, and deploying
an information system. It is composed of a number of clearly defined and distinct work
phases which are used by systems engineers and systems developers to plan for, design,
build, test, and deliver information systems. SDLC aims to produce high quality systems
that meet or exceed customer expectations, based on customer requirements, by
delivering systems which move through each clearly defined phase, within scheduled
time-frames and cost estimates. These stages can be characterized and divided up in
different ways, including the following.
 Preliminary analysis: The objective of phase 1 is to conduct a preliminary analysis,
propose alternative solutions, describe costs and benefits and submit a preliminary plan
with recommendations.
Conduct the preliminary analysis: in this step, you need to find out the organization's
objectives and the nature and scope of the problem under study. Even if a problem refers
only to a small segment of the organization itself then you need to find out what the
objectives of the organization itself are. Then you need to see how the problem being
studied fits in with them.
Propose alternative solutions: In digging into the organization's objectives and specific
problems, you may have already covered some solutions. Alternate proposals may come
from interviewing employees, clients, suppliers, and/or consultants. You can also study
what competitors are doing. With this data, you will have three choices: leave the system
as is, improve it, or develop a new system.
Describe the costs and benefits.
 Systems analysis, requirements definition: Defines project goals into defined functions
and operation of the intended application. Analyzes end-user information needs.

2.  Systems design: Describes desired features and operations in detail, including screen
layouts, business rules, process diagrams, pseudo code and other documentation.
 Development: The real code is written here.
 Integration and testing: Brings all the pieces together into a special testing environment,
then checks for errors, bugs and interoperability.
 Acceptance, installation, deployment: The final stage of initial development, where the
software is put into production and runs actual business.
 Maintenance: During the maintenance stage of the SDLC, the system is assessed to
ensure it does not become obsolete. This is also where changes are made to initial
software. It involves continuous evaluation of the system in terms of its performance.
 Evaluation: Some companies do not view this as an official stage of the SDLC, but is it
an important part of the life cycle. Evaluation step is an extension of the Maintenance
stage, and may be referred to in some circles as Post-implementation Review. This is
where the system that was developed, as well as the entire process, is evaluated. Some of
the questions that need to be answered include: does the newly implemented system meet
the initial business requirements and objectives? Is the system reliable and fault-tolerant?
Does the system function according to the approved functional requirements. In addition
to evaluating the software that was released, it is important to assess the effectiveness of
the development process. If there are any aspects of the entire process, or certain stages,
that management is not satisfied with, this is the time to improve. Evaluation and
assessment is a difficult issue. However, the company must reflect on the process and
address weaknesses.
b) Problems that are commonly associated with the traditional SDLC
 The long development cycle increases the possibility that by the time the system is
delivered, business changes may have invalidated the initial design or that the project
champions may have left the company or been reassigned, taking with them the impetus
for the project.

3.  The customer is involved only periodically, rather than being an active participant
throughout the project. This can result in misunderstandings on both sides: IT and the
customer.
 It is difficult for the customer to identify all requirements early in the project; however,
the sequential “river of no return” approach dictates this. The philosophy of the SDLC
means that there are no easy ways to mitigate this problem and still remain true to the
methodology.
C) Incremental Waterfall – The incremental waterfall methodology has the same first three to
four phases as the traditional waterfall model, but it deviates for phases five through ten by
creating mini releases and segmenting requirements into an incremental series of products, each
of which is developed fairly independently from the others. Incremental waterfall is highly
dependent on the development of a complete up front set of requirements, designed and
implemented in a series of smaller projects or releases. Each increment adheres to the waterfall
sequence.
d) The incremental waterfall methodology’s benefits include:
 Lower cost and less time required for first release
 Focus on essential requirements, thereby reducing the amount of unnecessary
functionality
 Less risk inherent in developing smaller, more manageable systems represented by
increments
 Possible reduction in the number of developers
 Possible decrease of user requirement changes because of the faster time to first release
 Possibility for incremental funding
 Phase-level control

4. Question Two
Read and understand the following narrative description. Required: draw a context DFD for the
portion of the narrative described below.
The purpose of the TEXTBOOK INVENTORY SYSTEM at a campus bookstore is to supply
textbooks to students for classes at a local university. The university’s academic departments
submit initial data about courses, instructors, textbooks and projected enrollments to the
bookstore on a TEXTBOOK MASTER LIST. The bookstore generates a PURCHASE ORDER,
which is sent to publishing company’s supplying textbooks. Book orders arrive at the bookstore
accompanied by a PACKING SLIP, which is checked and verified by the receiving department.
Students fill out a BOOK REQUEST that includes course information. When they pay for their
books the students are given a SALES RECEIPT.
STUDENTS
ACADEMIC
DEPARTMENTS
TEXTBOOK
INVENTORY
PUBLISHING
COMPANIES
Packing slip
(accompanying order)
Textbook master list
Book Request
Sales Receipt
Purchase
Orders

5. Question Three
Draw a flow chart to add the first ten numbers
Start
Sum=0
SUM=SUM+N
N=0
N=N=1
N<10
DISPLAY
SUM
END

6. Draw a flow chart and a structured English (pseudo code) from the following scenario
Calculate the bonus of employees based on the following policy “Female employees are
paid 7% of their basic salary while their male counterparts are paid 5% of their basic
salary”
IF Gender is male
Then Bonus is 7% of Basic salary
ELSE
Bonus is 5% of Basic Salary
END IF
Y N
a)
b) Draw a structured English (pseudo code), decision table and decision tree from the
following scenario
START
END
INPUT BASIC SAL AND GENDER
Display Bonus
GENDER=
FEMALE
Bonus=7%*Basi
c salary
Bonus=5%*Ba
sic salary

7. Student are awarded the following grades
i. If the pass mark is less or equal to forty = Fail
ii. If the pass mark is 41 and less or equal to 60 = Pass
iii. It the mark is 61 and less or equal to 85 = Merit
Over and 86 = Distinction.
Pseudo code
IF Marks < 41 Grade is Fail
ELSE IF Marks > 40
AND IF Marks < 61 Grade is Pass
ELSE IF Marks >61
AND IF Marks < 86 Grade is Merit
ELSE Grade is Distinction
END IF
Decision Tree
FAIL 1. MARKS <41
Y 2. MARKS< 61
PASS 3. MARKS<86
N Y
N
Y MERIT
N
DISTICTION
1
2
3

8. DECISION TABLE
RULES 1 2 3 4
Marks<41 Y N N N
Marks<61 Y Y N N
Marks<86 Y Y Y N
Marks>85 Y Y Y Y
Action
Fail X
Pass X
Merit X
Distinction X