Question

a student scored 83 and 88 on her first two quizzes write and solve a compund inequality to find the possible values for a third quiz score that would give her a average between 85 and 90 inclusive. please help

Answer 1

Let x be the score on the third quiz.

To find the average between 85 and 90 inclusive, we need the sum of the three quiz scores to be between 255 and 270 inclusive.

The sum of the three quiz scores is 83 + 88 + x = 171 + x.

So, we can write the compound inequality:

85 ≤ (171 + x)/3 ≤ 90

Multiplying both sides by 3:

255 ≤ 171 + x ≤ 270

Subtracting 171 from all sides:

84 ≤ x ≤ 99

Therefore, the possible values for the score on the third quiz are between 84 and 99, inclusive, in order to achieve an average between 85 and 90, inclusive.