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It is provided that Yoonie reviews $16$of the employees with an average time of $4$hours and a standard deviation of $1.2$hours. We have to find the probability that Yoonie will take $3.5$to $4.25$hours for one review and graph it.

According to the information, we have to find the probability that one review will take Yoonie from 3.5 to 4. 25

The Computation of the probability is given as below:

$p(3.5<x<4.25)=p(Z<\frac{4.5−\mathrm{μ}}{\mathrm{σ}})−p(Z<\frac{3.5−\mathrm{μ}}{\mathrm{σ}})$

$=p(Z<\frac{4.25−4}{1.2})−p(Z<\frac{3.5−4}{1.2})$

$=p(Z<0.21)−p(Z<−0.42)$

Therefore,

localid="1648621489396" $p(z<0.21)$and

$p(Z<−0.42)\text{in Excel is:}$

Therefore,

$p(3.5<x<4.25)=p(Z<0.21)−p(Z<−1.42)$

$=0.5832−0.3372$

=$0.2459$

The shaded region corresponding to the probability is as shown below:

It is provided that Yoonie reviews $16$of the employees with an average time of $4$hours and a standard deviation of$1.2$ hours

The probability is

$p(3.5<x<4.25)=p(Z<0.21)−p(Z<−1.42)$

$=0.5832−0.3372$

Simplify,

localid="1648621737422" $=0.2459$