Gantt chart: task dependencies

Name:

Date:

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Quick Questions

Shade in the A or B circle for each question.

1. In a dependency, which task must be finished first?

A The predecessor

B The successor

2. Which statement describes a finish-to-start dependency?

A Task B cannot start until Task A finishes

B Task B cannot finish until Task A starts

3. A Gantt chart shows a dependency between two tasks using:

A A diamond at the end of a task bar

B An arrow from one task bar to the other

4. A team must finish 'Design the database' before they can start 'Build the database'. 'Build the database' is the:

A Predecessor

B Successor

5. Which pair of tasks has a dependency?

A Write the code, then test the code

B Draw the logo, then book a meeting room

Match the Pairs

Draw a line connecting each item on the left to its match on the right.

Left column		Right column
1Task B depends on Task A		AThe successor task cannot start until the predecessor task has finished.
2Finish-to-start (FS)		BTest program (successor of Code program)
3A dependency arrow on a Gantt chart runs from the predecessor to the successor		CIf one task is a successor, it must be linked to its predecessor by a dependency, so it cannot run at the same time with no arrow.
4A successor task is the task that has to wait for another task to be complete		DDesign screens ──> Code interface
5Code interface ──> Design screens (arrow points back to the earlier task)		ETask A is the predecessor and Task B is the successor, so B cannot start or finish until A is complete.
6Write SRS (predecessor) and Draw context diagram (successor) run at the same time, with no link		FThe arrow is drawn backwards. A dependency arrow should run from the predecessor (Design screens) to the successor (Code interface).

Definitions

dependency

Fill in the Blanks

Complete each line of code by filling in the missing parts.

Design -> Code Link type: _______________

Design -> Code Design is the ___________ task

Design -> Code Code is the _________ task

Task 2 _______ on Task 1

Dependency arrow: Design __ Code

Spot the Error

Shade in the letter of the line that contains an error.

Question 1

A A Gather requirements: day 1-3

B B Design screens: day 2-5

C A -> B finish-to-start

Question 2

A Task A: Write code

B Task B: Test code

C B is the predecessor of A

Question 3

A A: Create database

B B: Load test data

C A depends on B

D Arrow points from A to B

Question 4

A FS: B starts when A starts

B Task A: Code login screen

C Task B: Test login screen

Question 5

A T1: Build login page

B T2: Test login page, after T3

C T3: Fix bugs, after T2

Answer Key

Gantt chart: task dependencies

Section A: Quick Questions

A — The predecessor

A — Task B cannot start until Task A finishes

B — An arrow from one task bar to the other

B — Successor

A — Write the code, then test the code

Section B: Match the Pairs

Task B depends on Task A → Task A is the predecessor and Task B is the successor, so B cannot start or finish until A is complete.

Finish-to-start (FS) → The successor task cannot start until the predecessor task has finished.

A dependency arrow on a Gantt chart runs from the predecessor to the successor → Design screens ──> Code interface

A successor task is the task that has to wait for another task to be complete → Test program (successor of Code program)

Code interface ──> Design screens (arrow points back to the earlier task) → The arrow is drawn backwards. A dependency arrow should run from the predecessor (Design screens) to the successor (Code interface).

Write SRS (predecessor) and Draw context diagram (successor) run at the same time, with no link → If one task is a successor, it must be linked to its predecessor by a dependency, so it cannot run at the same time with no arrow.

Section C: Definitions

dependency — A link between two tasks where one cannot start or finish until the other is complete. The first is the predecessor, the next is the successor. Shown on a Gantt chart by an arrow.

Section D: Fill in the Blanks

Design -> Code Link type: finish-to-start

Design -> Code
Design is the predecessor task

Design -> Code
Code is the successor task

Task 2 depends on Task 1

Dependency arrow: Design -> Code

Section E: Spot the Error

B — With a finish-to-start dependency, successor B cannot begin until predecessor A finishes on day 3. B must start on day 4 (day 4-7), not day 2.

C — Testing can only happen once the code is written, so A (Write code) is the predecessor and B is the successor. The line should say B is the successor of A.

C — Test data cannot be loaded until the database exists, so B depends on A. The dependency is written backwards, and it should read B depends on A.

A — Finish-to-start (FS) means the successor starts only after the predecessor finishes. Saying B starts when A starts describes a start-to-start link instead.

B — T3 already depends on T2, so making T2 depend on T3 creates a circular dependency. Neither task could ever start. T2 should come after T1.