: Consider the PERT network, C D O C 10-12-15 7-9-12 as shown below. The duration estimate for each activity A Finish is given in the notation o-m-p, where: o - optimistic, 8-11-15 K 19-24-30 m - most likely (mode), p - pessimistic. The estimate times are given in weeks. What is the probability that 4-5-7 3-5-6 this project will be completed in 81 weeks? Start 10-13-17 15-18-21 18-20-23 8-11-15 Probabilty Table on the next page -> O Task to tm to te var ES LS TF A B D E H 4 K Critical Path and its duration:To interpolate the y, value: X1, X3, y, and y? need to be entered/copied from the table. 6 x, defines the point to perform the interpolation. y, is the interpolated value and solution 02=((1p - to)/6))2 X1 y1 Es = (Is - Te)/Or Solving for yz Xy y2 Or = (02c + 03D + 03F + ... ) 1/2 (x2 - x1 )()'3 - )1 + y (X3 - X] ) *3 y3 Depends on the critical path Z Probability Z Probability Z Probability -3.0 0.1% -1.0 15.9% 1.0 84.1% -2.9 0.2% -0.9 18.4% 1.1 86.4% -2.8 0.3% -0.8 21.2% 1.2 88.5% -2.7 0.3% -0.7 24.2% 1.3 90.3% -2.6 0.5% -0.6 27.4% 1.4 91.9% -2.5 0.6% 0.5 30.9% 1.5 93.3% -2.4 0.8% -0.4 34.5% 1.6 94.5% -2.3 1.1% -0.3 38.2% 1.7 95.5% -2.2 1.4% -0.2 42.1% 1.8 96.4% -2.1 1.8% -0.1 46.0% 1.9 97.1% -2.0 2.3% 0.0 50.0% 2.0 97.7% -1.9 2.9% 0.1 54.0% 2.1 98.2% -1.8 3.6% 0.2 57.9% 2.2 98.6% -1.7 4.5% 0.3 61.8% 2.3 98.9% -1.6 5.5% 0.4 65.5% 2.4 99.2% -1.5 6.7% 0.5 69.1% 2.5 99.4% -1.4 8.1% 0.6 72.6% 2.6 99.5% -1.3 9.7% 0.7 75.8% 2.7 99.7% -1.2 11.5% 0.8 78.8% 2.8 99.7% -1.1 13.6% 0.9 81.6% 2.9 99.8% -1.0 15.9% 1.0 84.1% 3.0 99 9%