Question

ssuming the trend that exists in the data set below applies to all students, how long should Trevor study if he want to get at least a 75% on the test?

Time Spent Studying (minutes)
Grade on Test (%)
0
13
0
56
30
39
30
47
30
72
60
51
60
77
90
87
90
77
120
90
120
98
120
100
120
80
180
88
180
97
A.
at least 10 minutes
B.
at least 60 minutes
C.
at least 120 minutes
D.
at least 180 minutes

Answer 1

C.

At 120 minutes the recorded scores are 90, 98, 100 and 80 — all at least 75. Shorter times (e.g. 60 minutes) include scores below 75, so Trevor should study at least 120 minutes.