An agricultural field trial compares the yield of two varieties of corn. The researchers divide in half each of 14 fields of land in different locations and plant each corn variety in one half of each plot. After harvest, the yields are compared in bushels per acre at each location. The 14 differences (Variety A - Variety B) give x¯=3.5 and s=2.15. Does this sample provide evidence that Variety A had a higher yield than Variety B?

(a) State the null and alternative hypotheses:

H0 :

Ha :

(b) Find the test statistic, t =

(c) Answer the question: Does this sample provide evidence that Variety A had a higher yield than Variety B? (Use a 5% level of significance)