Scott X1 93430 S1 5602 n135 Ligonier X1 98043 S14731 n2 40So
Scott: X1 93430, S1= 5602, n1=35
Ligonier: X1= 98043, S1=4731 n2= 40
Solution
Let mu1 be the mean for Scott
Let mu2 be the mean for Ligonier
Ho: mu1=mu2 (i.e. null hypothesis)
Ha: mu1<mu2 (i.e. alternative hypothesis)
The test statistic is
Z=(xbar1-xbar2)/sqrt(s1^2/n1+s2^2/n2)
=(93430-98043)/sqrt(5602^2/35+4731^2/40)
=-3.82
It is a left-tailed test.
Given a=0.01, the critical value is Z(0.01) =-2.33 (from standard normal table)
Since Z=-3.82 is less than -2.33, we reject the null hypothesis.
So we can conclude that Ligonier is significantly more expensive to live in as compared to Scott.

