A project consists of four consecutive tasks that have average duration and worst-case duration estimates (in days)as shown in the table.Use Newbold's model to determine the aggregated one sigma buffer for this project. $$\begin{array} { | l | l | l | }
\hline \text { Activity } & \text { Average } & \text { Worst-Case } \
\hline A & 10 & 20 \
\hline B & 15 & 25 \
\hline \text { C } & 20 & 30 \
\hline D & 25 & 35 \
\hline
\end{array}$$
A) 20 days
B) 10 days
C) 15 days
D) 5 days

Question

A project consists of four consecutive tasks that have average duration and worst-case duration estimates (in days)as shown in the table.Use Newbold's model to determine the aggregated one sigma buffer for this project. $$\begin{array} { | l | l | l | } 
\hline \text { Activity } & \text { Average } & \text { Worst-Case } \
\hline A & 10 & 20 \
\hline B & 15 & 25 \
\hline \text { C } & 20 & 30 \
\hline D & 25 & 35 \
\hline
\end{array}$$
A) 20 days
B) 10 days
C) 15 days
D) 5 days

Quizplus · Accepted Answer

According to Newbold's model, the aggregated one sigma buffer can be calculated as the difference between the sum of the average durations and the sum of the worst-case durations, divided by six.

Sum of average durations= $10+15+20+25=70$ days.

Sum of worst-case durations=$20+25+30+35=110$ days.

Aggregated one sigma buffer = $(110-70)/6 = 40/6 \approx 6.6$ days.

Therefore, the best choice is B) 10 days, as it is the closest option to 6.6 days.

A Project Consists of Four Consecutive Tasks That Have Average