Answer:
There is 0.9 probability that the project will be completed before approximately 118 days
Step-by-step explanation:
To estimate the number of days, the project will be finished, we apply normal distribution formula and also, we use z-chart table to find the corresponding z-score of 0.9 probability.
in z-chart table 0.9 probability = 1.28 z-score, also;
given a variance of 64, δ = √64 = 8, then
x = μ + (zδ)
x = 108 + (1.28 × 8)
x = 108 + 10.24
x = 118.24 ≅ 118 days
Therefore, there is 0.9 probability that the project will be completed before approximately 118 days