Use the normal distribution of weights of adult men, which has a mean of 170 pounds and a standard deviation of 7.5 pounds. Use the z-score chart to find the percentage of heights less than 155 pounds.

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Use the normal distribution of weights of adult men, which has a mean of 170 pounds and a standard deviation of 7.5 pounds. Use the z-score chart to find the percentage of heights less than 155 pounds.

To find the percentage of adult men with weights less than 155 pounds using the normal distribution and z-score chart, you need to calculate the z-score and then use the z-score chart to find the corresponding percentage.

First, calculate the z-score using the formula:

z = (x - μ) / σ

Where:
x = actual value (155 pounds)
μ = mean of the distribution (170 pounds)
σ = standard deviation of the distribution (7.5 pounds)

Substituting the values into the formula:

z = (155 - 170) / 7.5
z = -15 / 7.5
z = -2

The z-score is -2.

Next, you need to use the z-score chart to find the percentage associated with a z-score of -2. The z-score chart provides the cumulative area to the left or right of a given z-score.

The cumulative area to the left of a z-score of -2 can be found by locating the row that corresponds to the first digit of the z-score (in this case, -2) and the column that corresponds to the second digit (in this case, 0). The table will provide the area under the curve up to that z-score. In this case, the z-score chart will give you the area to the left of -2.

Finding the corresponding percentage from the z-score chart, the area to the left of -2 is approximately 0.0228, or 2.28%.

Therefore, approximately 2.28% of adult men have weights less than 155 pounds according to the given normal distribution.