Question

The department of public safety has an old memo stating the number of varies according to a normal distribution, with a population mean of 2.2 and a population standard deviation of 1.4 Department officials implemented a new safety plan to see if they could reduce the average intersection. They record the number of accidents per week for 52 weeks, n is 52, and find the accidents per week over that period is 2, sample mean is 2 confirm with a P-value test of Ho: μ 2.2 against H1: μ < 2.2 15. accidents per week at a hazardous intersection number of accidents at this average number of , accidents per week. Do a Z-Test with an α .05 and

Answer 1

z = (x -mean)/(s/sqrt(n))
= ( 2 - 2.2)/(1.4/sqrt(52))
= -1.0302

p value = 0.1515

do not reject H0