Question

Penndot claims that the standard deviation of the speed of drivers in the streets of the Historical Downtown of the Greater Bradford Metropolitan Area is 8 miles per hour for all vehicles. Your uncles and aunts, who have a responsibility to uphold the virtues of speeding feel that Penndot’s estimate is low. A survey is conducted by UPB students and for 50 randomly selected drivers, the standard deviation is 10.5 miles per hour. Is Penndot’s claim believable ? Is this a right-tail, left-tail or a two-tail test ? Use α=0.05.

Answer 1

Given data r = 8 S =10.5 a=0.05 0 250 Hoo r=8 Hii o>8 (Right Tail (n-1) 89 49x10.52 G2 5402.25 64 82 84.410 X² - 84.410 df = not 50r1=49 P-vaker P[x² = 84.410 49 using Excel = CHISQ-DIST- RT (84.410,49 = 0.00125 P = 0.0013 P. La=0.05 Reject Ho here is sufficient evidence to support the claim that standard deviation of the speed of drivers in the Streets of the historical downtown of the greater Bradford metropolitan Area is smites per hour for all vehicles