Question

Does age affect the standard deviation of the stride distance, measured in centimeters (cm), of Aquarius remigis, the common waterstrider? In a simple random sample of five adult water striders, the standard deviation in stride distance is 1.0374 cm. The sample standard deviation in stride distance among ten randomly selected newborn striders is 0.3808 cm.

Assume that stride distance is normally distributed in each population.

Compute an ?

‑statistic to test for equality of two population standard deviations. Report your answer to two decimal places.

?=

Answer 1

Let be the true/population standard deviationof the stride distance, of adult water striders and be the true standard deviationof the stride distance, of newborn water striders

We want ot test for equality of two population standard deviations.

The hypotheses are

We have the following sample information

The test statistic is

ans: ?‑statistic to test for equality of two population standard deviations is

F=7.42