Question

Birth Weight Data Set 1 “Body Data” in Appendix B includes birth weights of 195 males, and the summary statistics are x = 3272.8 g and s = 660.2 g. Use a 0.01 significance level to test the claim that the population of birth weights of males is less than 3400 g.

Answer 1

H0: >= 3400

Ha: < 3400

Test statistics

t = - / S / sqrt(n)

= 3272.8 - 34400 / 660.2 / sqrt(195)

= -2.69

This is test statistics value.

Critical value at 0.01 level with 194 df  = -2.346

Since test statistics < -2.346, we have sufficient evidence to reject H0.

We conclude at 0.01 level that we have enough evidence to support the claim.