Question

A metropolitan transportation authority has set a bus mechanical reliability goal of 3,800 bus miles. Bus mechanical reliability is measured specifically as the number of bus miles between mechanical road calls. Suppose a sample of 100 buses resulted in a sample mean of 3,825 bus miles and a sample standard deviation of 175 bus miles. Complete parts​ (a) and​ (b) below.

Answer 1

Solution :

= 3,800

=3,825

S =175

n = 100

This is the two tailed test .

The null and alternative hypothesis is ,

H0 :    =3,800

Ha :     3,800

Test statistic = t

= ( - ) / S / n

= (3,825 -3,800) / 175 / 100

= 1.428

Test statistic = t= 1.428

P-value =0.1564