Are Canadians getting fatter? Researchers interested in this question take a random sample of 500 people and record an average weight of 86 kg.Ten years ago,the average weight was 83 kg. A) $\mathrm { H } _ { 0 }$ : ? = 86 $\mathrm { H } _ { \mathrm { A } }$ : ? 83 C) $\mathrm { H } _ { 0 }$ : ? = 86 $\mathrm { H } _ { \mathrm { A } }$ : ? 86 D) $\mathrm { H } _ { 0 }$ : ? = 83 $\mathrm { H } _ { \mathrm { A } }$ : ?

Question

Are Canadians getting fatter? Researchers interested in this question take a random sample of 500 people and record an average weight of 86 kg.Ten years ago,the average weight was 83 kg. A) $\mathrm { H } _ { 0 }$ : ? = 86 $\mathrm { H } _ { \mathrm { A } }$ : ? < 86 B) $\mathrm { H } _ { 0 }$ : ? = 83 $\mathrm { H } _ { \mathrm { A } }$ : ? > 83 C) $\mathrm { H } _ { 0 }$ : ? = 86 $\mathrm { H } _ { \mathrm { A } }$ : ? > 86 D) $\mathrm { H } _ { 0 }$ : ? = 83 $\mathrm { H } _ { \mathrm { A } }$ : ? < 83 E) $\mathrm { H } _ { 0 }$ : ? = 83 $\mathrm { H } _ { \mathrm { A } }$ : ? ? 83

Quizplus · Accepted Answer

We can use a one-tailed hypothesis test with the null hypothesis being that the average weight is still 83 kg (μ=83) and the alternative hypothesis being that the average weight has increased (μ>83). 
Since the sample average weight is 86 kg, which is higher than the null hypothesis value, we can reject the null hypothesis and conclude that the average weight has increased in the past ten years. Out of the given answer choices, only B matches this conclusion.

Are Canadians Getting Fatter? Researchers Interested in This Question Take H0\mathrm { H } _ { 0 }H0​

Are Canadians Getting Fatter? Researchers Interested in This Question Take $\mathrm { H } _ { 0 }$