# Question

A pediatrician's records showed the mean height of a random sample of 25 girls at age 12 months to be 29.530 inches with a standard deviation of 1.0953 inches.

(a) Construct a 95 percent confidence interval for the true mean height.

(b) What sample size would be needed for 95 percent confidence and an error of ±.20 inch? (Data are from a project by statistics students Lori Bossardet, Shannon Wegner, and Stephanie Rader.)

(a) Construct a 95 percent confidence interval for the true mean height.

(b) What sample size would be needed for 95 percent confidence and an error of ±.20 inch? (Data are from a project by statistics students Lori Bossardet, Shannon Wegner, and Stephanie Rader.)

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