Question

State the null and alternative hypotheses for each of the situations

a. A quality control engineer is testing the battery life of a new smartphone. The company is

advertising that the battery lasts 24 hours on a full - charge, but the engineer suspects that the battery life is actually

less than that. They take a random sample of 50 of these phones to see if their average battery life is significantly less than 24 hours. Let μ represent the mean battery life for this population of phones.

b. healthcare providers saw that 48% of their members received their flu shot in recent years. The healthcare provider then tried a more aggressive advertising strategy in the following year hoping to increase the proportion. Afterward, the provider took a sample of members to test if the proportion who received their flu shot had changed according to their predictions.

Answer 1

a.  The null and alternative hypotheses

Let μ represent the mean battery life for this population of phones.

Null hypothesis

i.e. the mean battery life for this population of phones is equal to 24 hours on a full - charge.

Alternative hypothesis

i.e. the mean battery life for this population of phones is less than 24 hours on a full - charge.

b. The null and alternative hypotheses

Let p represent the population proportion of members who received their flu shot.

Null hypothesis

i.e. the population proportion of members who received their flu shot is equal to 48%

Alternative hypothesis

i.e. the population proportion of members who received their flu shot is greater than 48%

Let me know in the comments if anything is not clear. I will reply ASAP! Please do upvote if satisfied!