Question $36(2$ points$)$

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An activity on a PERT network has these time estimates: optimistic $=2,$ most likely $=3,$ and pessimistic $=8.$ Its expected time and variance $($if it is a critical activity$)$ are

Question $36$ options:

$43\mathrm{.}3$; $1.$

$4\mathrm{.}33$; $6.$

$4\mathrm{.}33$; $1.$

$3\mathrm{.}67$; $6.$

$3\mathrm{.}67$; $1.$

Question $37(2$ points$)$

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A PERT project has $45$ activities, $19$ of which are on the critical path. The estimated time for the critical path is $120$ days. The sum of all activity variances is $64,$ while the sum of variances along the critical path is $36.$ The probability that the project can be completed between days $108$ and $120$ is

Question $37$ options:

$0\mathrm{.}0227.$

$0\mathrm{.}1058.$

$0\mathrm{.}9773.$

$0\mathrm{.}4773.$

$-2\mathrm{.}00.$

Question $38(2$ points$)$

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An activity on a PERT network has these time estimates: optimistic $=2,$ most likely $=5,$ and pessimistic $=10.$ Its expected time is

Question $38$ options:

$5\mathrm{.}00.$

$0\mathrm{.}533.$

$5\mathrm{.}33.$

$5\mathrm{.}67.$

$17\mathrm{.}00.$

Question $39(2$ points$)$

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If an activity whose normal duration is $13$ days can be shortened to $10$ days for an added cost of $$1,500,$ the crash cost per period is

Question $39$ options:

$$1,500.$

$$500.$

$$13,000.$

$$750.$

$$15,000.$

Question $40(2$ points$)$

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A project being analyzed by PERT has $50$ activities, $12$ of which are on the critical path. If the estimated time along the critical path is $176$ days with a project variance of $144,$ the probability that the project will take $194$ days or less to complete is

Question $40$ options:

$2\mathrm{.}00.$

$0\mathrm{.}0668.$

near zero.

$0\mathrm{.}9332.$

$0\mathrm{.}0126.$