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A particular brand of potato chips is approximately Normal with

The mean is$9.12$

The standard deviation is$0.05$

The weight distribution is approximately $N(9.12,0.05)$. The Normal density curve is sketched below, with the necessary spots labelled.

By the $68-95-99.7$rule, approximately $2.5\%$of bags weigh less than $9.02$ounces, because $9.02$is two standard deviations below the mean.

As a result, about $2.5\%$of bags weigh less than $9.02$ounces.

A particular brand of potato chips is approximately Normal with

The mean is $9.12$

Standard deviation is$0.05$

Approximately $68\%$of bags had weights between $9.12-0.05=9.07$and $9.12+0.05=9.17$ounces, according to the $68-95-99.7$standards.

As a result, roughly $68\%$of bags had a weight of $9.07$ounces to $9.17$ounces.

A particular brand of potato chips is approximately Normal with

The mean is $9.12$

Standard deviation is$0.05$

Because $9.17$is one standard deviation above the mean, according to the $68-95-99.7$rule, about $84\%(0.68+0.16)$of bags have weights less than $9.17$ounces. Because $8.97$is three standard deviations below the mean, approximately $0.15\%$of bags weigh less than $8.97$ounces. As a result, about $84\%-0.15\%=83.85\%$of bags weigh between $8.97$and $9.17$ounces.

As a result, $83.385\%$of the bags weigh between $8.97$and $9.17$ounces.

A particular brand of potato chips is approximately Normal with

The mean is $9.12$

Standard deviation is$0.05$.

Then $9.07$is one standard deviation below the average.

The area to the left of $9.07$is therefore $0.16$. In other words, the $16$th percentile of the weights of these potato chips packages is$9.07$.