Question

A major manufacturer of golf equipment has designed a new model of golf ball with a cut resistant coating. However there is a question concerning the mean driving distance in yards of the new model golf balls as compared to their older model. A sample of each type of golf ball is tested for driving distance and the results are found in the table below. Test to see if the mean driving distance is changed by the new coating and report your finding. Use 99% confidence for this test. (z test: 2 samples for means)

Current Model New Model

Current Model	New Model
n 1 = 40	n 2 = 40
x bar 1 = ______	x bar 2 = ______
σ 1 2 = 77	σ 2 2 = 98

When Z = 1.326

Answer 1

we have to test whether the mean driving distance is changed by the new coating, so it is a two tailed hypothesis test

Using the data table, the observed z statistic is given as

z = 1.326

now, using z table to find the p value

check 1.3 in the left most column and then find 0.03 in the top row, select the intersecting cell

we get

p value = 0.1848

significance level = 1- confidence level = 1-0.99 = 0.01

we can see that the p value is greater than significance level of 0.01

so, result is insignificant and we failed to reject the null hypothesis

Therefore, there is insufficient evidence to conclude that the mean driving distance is changed by the new coating