Question

Jean's scores on the first three of four 100-point tests were 82, 86, and 91. what score must she receive on the fourth test to have an average of at least 87 points for all the tests

Answer 1

The total for an average to be 87 would have be 87 x the number of tests or 87 x 4 = 348.

Let's see the total for her previous 3: 82 + 86 + 91 = 259

The 4th one needs to take her from 259 to 348.

348 - 259 = 89. she has 89 'to go" to get that 87 average.

She requires an 89 to achieve an 87 test average.