What minimum grade would the student need to achieve on the last test to get an 80% average?

A dataset can contain a range of values that depict a certain characteristic, such as grades on tests in a class during the semester. A specific student has so far received the following grades: 76,81, 78, 87, 75, and 72. There is one final test in the semester.

What minimum grade would the student need to achieve on the last test to get an 80% average?
A . 82
B . 89
C . 91
D . 94

View Answer

Answer: C

Explanation:

To calculate the minimum grade needed to achieve an 80% average, we can use the following formula:

minimum grade = (target average * number of tests – sum of grades) / (number of tests – 1)

Plugging in the given values, we get:

minimum grade = (80 * 7 – (76 + 81 + 78 + 87 + 75 + 72)) / (7 – 6)

minimum grade = (560 – 469) / 1

minimum grade = 91

Therefore, the student needs to score at least 91 on the last test to get an 80% average.