I’m running some sort of question as below which ready need advice or assist
A national TV telethon committee is interested in determining whether donations given by males have greater variability in amount than do the donations of females. To test this, random samples of 25 males and 25 females were selected from people who donated during last years telethon. The following statistics were computed from the sample data:
Males
x -$l2.4, s=$2.5
Femalesx = $8.92 , s=$1.34
a. State the null and altei-native hypotheses to be tested.b- Based on a significance level of 0.05, do donations from males have greater variability than do the donations of females?
A company is considering including pre-addressed return envelopes in its monthly bills to customers with the goal of reducing ti-ic mean time until payment is received, which is currently 15.8 days. As an experiment, 150 randomly selccted customers were provided with a pre-addressed return envelope in their next bill. The sample mean time until payment was received was 14.8 days, and the standard deviation was 6.4 days, Is there evidence the inclusion of the pre-addressed return envelope had the desired effect? Test using a 0:05 level ofsignificance.
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