Question

Roger spent 45 minutes studying for the test. Assuming the trend that exists in the data set below applies to Roger as well, approximately which grade should Roger expect to receive on the test? Time Spent Studying (minutes) Grade on Test (%) 0 28 0 54 30 45 30 39 30 63 60 53 60 75 90 85 90 78 120 92 120 100 120 98 120 89 180 99 180 95

Answer 1

He would more than likely receive a 60%

Answer 2

60%

Explanation:

0 28

0 54

30 45

30 39

30 63

60 53

60 75

90 85

90 78

120 92

120 100

120 98

120 89

180 99

180 95

Using linear regression calculator

Equation : ŷ = 0.36805X + 42.6864

Now we are supposed to find which grade should Roger expect to receive on the test if he studies for 45 minutes.

Substitute x = 45

ŷ = 0.36805(45) + 42.6864

ŷ = 59.24865

So, Roger should expect 60% grade.