(Choose 1 answer)
(See picture)
A. 0.680
B. 0.242
C. 4.517
D. None of the other choices is correct
E. 4.523
Two suppliers manufacture a plastic gear used in a laser printer. The impact strength of these gears, measured in foot-pounds, is an important characteristic. A random sample of 18 gears from supplier 1 results in₁=310 and s₁=21, and another random sample of 14 gears from supplier 2 results inx=280 and s₂ =15. A researcher would like to test the claim that supplier 1 provides gears with higher mean impact strength. Use a significance level of 0.05, and assume that both populations are normally distributed with the same variance.Calculate the value of the test statistic.
the exam.
3
