Question

In a regional high school swim meet, women’s times (in seconds) in the 200-yard freestyle ranged from 108.5 to 140.6. Estimate the standard deviation, using the Empirical Rule. (Round your answer to 2 decimal places.)

Answer 1

Answer: Estimated the standard deviation α = 5.35

Explanation:

According to Empirical rule, the largest value is approximately:

ц + 3α

And the smallest value is approximately:

ц + 3α

Based on the given figures in the question, we can say

ц + 3α = 140.6

ц - 3α = 108.5

Now subtracting these two; we have

ц + 3α - ( ц - 3α ) = 140.6 - 108.5

ц + 3α - ц + 3α = 32.1

6α = 32.1

α = 32.1 / 6

α = 5.35

Estimated the standard deviation α = 5.35