Examveda
Examveda

If an activity has its optimistic, most likely and pessimistic times as 2, 3 and 7 respectively, then its expected time and variance are respectively

A. 3.5 and $$\frac{5}{6}$$

B. 5 and $$\frac{{25}}{{36}}$$

C. 3.5 and $$\frac{{25}}{{36}}$$

D. 4 and $$\frac{5}{6}$$

Answer: Option C


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Comments ( 2 )

  1. Animesh Das
    Animesh Das :
    4 years ago

    But In CPM method is shown the longest duration that means answer should be Maximum time

  2. Faisal Shafique
    Faisal Shafique :
    6 years ago

    expected time = [2 + 7 + 4(3) ]/6 = 3.5
    Variance = [(tp - to)/6]^2
    = [(7-2)/6]^2 = (5/6) ^ 2 = 25/36

    so right option is C

Related Questions on Construction Planning and Management

If to, tp and tm are the optimistic, pessimistic and most likely time estimates of an activity respectively, the expected time t of the activity will be

A. $$\frac{{{{\text{t}}_{\text{o}}} + 3{{\text{t}}_{\text{m}}} + {{\text{t}}_{\text{p}}}}}{2}$$

B. $$\frac{{{{\text{t}}_{\text{o}}} + 3{{\text{t}}_{\text{m}}} + {{\text{t}}_{\text{p}}}}}{3}$$

C. $$\frac{{{{\text{t}}_{\text{o}}} + 4{{\text{t}}_{\text{m}}} + {{\text{t}}_{\text{p}}}}}{4}$$

D. $$\frac{{{{\text{t}}_{\text{o}}} + 4{{\text{t}}_{\text{m}}} + {{\text{t}}_{\text{p}}}}}{5}$$

E. $$\frac{{{{\text{t}}_{\text{o}}} + 4{{\text{t}}_{\text{m}}} + {{\text{t}}_{\text{p}}}}}{6}$$