Question

danielle has test scores of 92, 86, 83, 90, and 91 in her math class. what score does she need on her next test to bring her average up to 90% (if possible)?

Answer 1

Answer: 98

Step-by-step explanation:

Let the test score be x

Recall,

mean or average score = sum of scores/number of scores

From the information given,

the scores are 92, 86, 83, 90, and 91. By adding x,

number of scores = 6

Mean score = 90

Thus, we have

(92 + 86 + 83 + 90 + 91 + x)/6 = 90

(442 + x)/6 = 90

By cross multiplying,

442 + x = 90 * 6 = 540

Subtracting 442 from both sides, we have

442 - 442 + x = 540 - 442

x = 98

She needs to score 98