QUANTITY ESTIMATION AND MANAGEMENT (RCE-503)
B.Tech | Semester V | Section-wise Important Questions & Notes
SECTION A – Very Short Answer (2 × 7 = 14 Marks)
This section tests basic definitions and concepts. Answers must be short and direct.
Important Questions
What is the use of a dummy activity in a network? What do you mean by a cash flow diagram?
Define critical path. What is float in network analysis?
Define bar chart. What is estimation?
Define rate analysis.
Key Notes
Dummy activity: Used in network diagrams to show dependency; consumes no time or resources.
Cash flow diagram: Shows inflow and outflow of money during project duration.
Critical path: Longest path in a network; decides total project duration.
Float: Extra time an activity can be delayed without affecting project completion.
SECTION B – Short Answer / Numerical (5–7 Marks)
This section includes theory + numericals, mainly from PERT/CPM and project planning.
Important Questions
Explain CPM and PERT techniques. Explain dummy activity with an example.
Explain cash flow analysis in construction projects. Describe bar chart and its limitations.
Explain total float, free float, and independent float.
Key Notes
CPM: Deterministic time estimates, used in construction.
PERT: Probabilistic, uses three-time estimates (to, tm, tp).
Bar chart: Simple planning tool but does not show dependency clearly.
Float calculations are very important numerically.
SECTION C – Long Answer / Numerical (High Weight)
This section is most scoring and usually includes network diagrams and probability questions.
Most Important Question
Calculate the time duration that will provide 90% probability of project completion
(using Z = 1.3 or 1.1 as given).
(Based on the PERT network diagram shown on Page 2)
Key Notes for Solving
Expected time:
- Te=to+4tm+tp6T_e = \frac{t_o + 4t_m + t_p}{6}Te=6to+4tm+tp
Variance:
- σ2=(tp−to6)2\sigma^2 = \left(\frac{t_p - t_o}{6}\right)^2σ2=(6tp−to)2
Probability equation:
- Z=T−TeσZ = \frac{T - T_e}{\sigma}Z=σT−Te
Always:
Find critical path
Add variances
Apply Z-value formula
