Question

The body mass index (BMI) of a person is the person’s weight divided by the square of his or her height. It is an indirect measure of the person’s body fat and an indicator of obesity. Results from surveys conducted by the Centers for Disease Control and Prevention (CDC) showed that the estimated mean BMI for US adults increased from 25.0 in the 1960–1962 period to 28.1 in the 1999–2002 period.

Suppose you are a health researcher. You conduct a hypothesis test to determine whether the mean BMI of US adults in the current year is lower than the mean BMI of US adults in 2000. Assume that the mean BMI of US adults in 2000 was 28.1 (the population mean). You obtain a sample of BMI measurements of 1,034 US adults, which yields a sample mean of M = 28.9. Let μ denote the mean BMI of US adults in the current year.

Required:
Formulate your null and alternative hypotheses by selecting the appropriate values in the blue dropdown menus that follow.

Answer 1

Answer:

The null hypothesis is  $H_o : \mu = 28.1$

 The alternative hypothesis is  $H_a : \mu < 28.1$

Step-by-step explanation:

From the question we are told that

   The population mean at 1960 - 1962 is  $\mu_1 = 25.0$

    The population mean at 1999- 2002 is  $\mu_2 = 28.1$

     The sample size is  n=  1034

     The sample mean is  $M = 28.9$

 The null hypothesis is  $H_o : \mu = 28.1$

 The alternative hypothesis is  $H_a : \mu < 28.1$