Question

using the frequency table below, find how many students received a score of 80 or better on a mathematics test.

score interval	frequency
60 - 69	5
70 - 79	4
80 - 89	4
90 - 100	3

a 11
b 8
c 7
d 4

Explanation:

Step1: Identify relevant intervals

Intervals are 80 - 89 and 90 - 100.

Step2: Sum frequencies

$4 + 3=7$

Answer:

C. 7