In a PERT network the activities on the critical path are...

Home / Mining Engineering / Mine System Engineering / Question

Examveda

In a PERT network, the activities on the critical path are a, b and c. The standard deviations of the durations of these activities are 2, 2 and 1 respectively. The variance of the project duration is

A. 3

B. 5

C. 9

D. 12

Answer: Option C

This Question Belongs to Mining Engineering >> Mine System Engineering

Join The Discussion

Related Questions on Mine System Engineering

Workmen arrive at a mine workshop to receive tools for maintenance. The inter-arrival time of workmen at the service counter is exponentially distributed with an average time of 10 min. The service time at the counter is also distributed exponentially with a mean time of 6 min. The average time spent by a workman waiting for his turn to be served in min is

A. 9

B. 12

C. 15

D. 18

View Answer

A mining project is composed of five activities whose three time estimates in months are given below:

Activity	Estimated duration (months)
	Optimistic time	Most likely time	Permissible time
1 - 2	1	1	7
1 - 3	2	5	8
2 - 4	1	1	7
3 - 4	2	5	14
4 - 5	3	6	15

The expected duration of the mining project in months is

A. 5

B. 16

C. 18

D. 29

View Answer

The failure data analysis of a longwall mining system consisting of thre major subsystems revealed that the failure rate of shearer, face conveyor any stage loader are 0.15/ hour, 0.2/ hour and 0.1/ hour respectively. If all the subsystems must be running for a satisfactory system operation, the reliability of the longwall system for a period of 4 hours is

A. 0.165

B. 0.259

C. 0.405

D. 0.63

View Answer

Consider the following linear programming problem:
Maximize z = 3x + 2y
s.t. 3x + 2y ≥ 15
2x + 3y ≤ 6
x ≥ 0, y ≥ 0
The above linear programming problem has

A. Unique optimal solution

B. Multiple optimal solution

C. Unbounded solution

D. Infeasible solution

View Answer

More Related Questions on Mine System Engineering