Answer:
Test Statistic = 10
Critical Value = 9.488
Step-by-step explanation:
Given :
Grade A _ B _ C _ D _ F
_____14 _ 18 _32_ 20_16
H0 : distribution of grade is uniform
H1 : Distribution of grade is not uniform
Using the Chisquare statistic :
χ² = (observed - Expected)² / Expected
The expected value :
(14+18+32+20+16) / 5 = 20
χ² = (14-20)^2 / 20 + (18-20)^2 / 20 + (32-20)^2 / 20 + (20-20)^2 / 20 + (16-20)^2 / 20
χ² statistic = 10
The χ² critical at df = (n - 1) = 5 - 1 = 4
χ² Critical(10, 4) = 9.488