• # question_answer Estimated time T, and variance of the activities 'V on the critical path in a PERT new work are given in the following table: Activity ${{\mathbf{T}}_{\mathbf{e}}}$ (days) V ${{\left( \mathbf{days} \right)}^{\mathbf{2}}}$ a 17 4 b 15 4 c 8 1 The probability of completing the project in 43 days is: A) 15.6%              B) 50.0%C) 81.4%              D) 90.0%

$\sum{{{T}_{e}}}=17+15+8=$40 days $\sum{V=4+4+1=9}$ $\sigma =\sqrt{\sum{V}}=\sqrt{9}=3$ ${{T}_{s}}\,=$ 43 days $z=\frac{{{T}_{s}}-{{T}_{e}}}{\sigma }=\frac{43-40}{3}=1$ For z = 1, P = 0.8143 or 81.43%