Question

Bags of flour at a local grocery store have a mean weight of 83 ounces with a standard deviation of 2 ounces. Which weight represents the 65th percentile?

A.82.2 ounces
B.82.5 ounces
C.83.5 ounces
D.83.8 ounces

Answer 1

D.83.8 ounces

Explanation:

The z score for 65th percentile = 0.385

Mean weight of 83 ounces with a standard deviation of 2 ounces

The formula for calculating a z-score is z = (x-μ)/σ

where x is the raw score

μ is the population mean

σ is the population standard deviation

x = ??

Hence:

0.385 = (x - 83)/2

Cross Multiply

0.385 × 2 = x - 83

0.77 = x - 83

x = 83 + 0.77

x = 83.77 ounces

Approximately = 83.8 ounces

Answer 2

D.83.8 ounces

Explanation:

The z score for 65th percentile = 0.385

Mean weight of 83 ounces with a standard deviation of 2 ounces

The formula for calculating a z-score is z = (x-μ)/σ

where x is the raw score

μ is the population mean

σ is the population standard deviation

x = ??

Hence:

0.385 = (x - 83)/2

Cross Multiply

0.385 × 2 = x - 83

0.77 = x - 83

x = 83 + 0.77

x = 83.77 ounces

Approximately = 83.8 ounces