Question

The National Health Statistics Reports described a study in which a sample of 86 one-year-old baby boys were weighed. Their mean weight was 25.6 pounds with standard deviation 5.3 pounds. A pediatrician claims that the mean weight of one-year-old boys differs from 25 pounds. Do the data provide convincing evidence that the pediatrician's claim is true? Use the =α0.01 level of significance and the P-value method and Excel. Part 1 of 5 (a)State the appropriate null and alternate hypotheses. H0: =μ25 H1: ≠μ25 This hypothesis test is a ▼two-tailed test. Part: 1 / 51 of 5 Parts Complete Part 2 of 5 (b)Compute the value of the test statistic. Round the answer to at least three decimal places. =t

Answer 1

To test whether the mean weight of one-year-old boys differs from 25 pounds, we need to perform a hypothesis test. The appropriate null and alternate hypotheses are: Null Hypothesis (H0): The mean weight (μ) of one-year-old boys is equal to 25 pounds. Alternate Hypothesis (H1): The mean weight (μ) of one-year-old boys differs from 25 pounds.

To test whether the mean weight of one-year-old boys differs from 25 pounds, we need to perform a hypothesis test. The appropriate null and alternate hypotheses are:

Null Hypothesis (H0): The mean weight (μ) of one-year-old boys is equal to 25 pounds.

Alternate Hypothesis (H1): The mean weight (μ) of one-year-old boys differs from 25 pounds.

To compute the test statistic, we can use the formula: test statistic = (sample mean - hypothesized mean) / (standard deviation / sqrt(sample size)).

Plugging in the values from the study:

Sample mean: 25.6 pounds

Hypothesized mean: 25 pounds

Standard deviation: 5.3 pounds

Sample size: 86

Calculating the test statistic:

test statistic = (25.6 - 25) / (5.3 / sqrt(86))

test statistic ≈ 1.652 (rounded to three decimal places).