The coach of an adult Master's Swim class selected eight swimmers within each of the two age groups shown below.A 50-yard freestyle time is recorded for each swimmer.The resulting times (seconds)are shown below.Which statistical test would you choose to compare the two groups?
A)t-test for independent samples with known variances
B)t-test for independent samples with unknown variances
C)t-test for paired samples
D)z-test for two independent proportions

Question

The coach of an adult Master's Swim class selected eight swimmers within each of the two age groups shown below.A 50-yard freestyle time is recorded for each swimmer.The resulting times (seconds)are shown below.Which statistical test would you choose to compare the two groups? 
A)t-test for independent samples with known variances 
B)t-test for independent samples with unknown variances 
C)t-test for paired samples 
D)z-test for two independent proportions

Quizplus · Accepted Answer

Since the variances are unknown, we would use a t-test for independent samples with unknown variances to compare the two age groups in terms of their 50-yard freestyle times.

The Coach of an Adult Master's Swim Class Selected Eight