Question

Your test scores in one class are 79 and 85. What possible scores can you earn on your next test to have a test average between 82 and 88​, ​inclusive?

Answer 1

85, 88, 91, 94, 97

Explanation:

83, 84, 85, 86, 87

83 × 3 = 249

79 + 85 = 164

249 - 164 = 85

84 × 3 = 252

252 - 164 = 88

85 × 3 = 255

255 - 164 = 91

86 × 3 = 258

258 - 164 = 94

87 × 3 = 261

261 - 164 = 97

Answer 2

Multiply the average by the number of tests to find the total of the scores:

82 x 3 = 246

88 x 3 = 264

The total of the three tests would need to be between 246 and 264

The total of the first two tests is 79 + 85 = 164

Subtract the total of the first two from the totals above:

246 - 164 = 82

264 - 164 = 100

The score of the third test needs to be between 82 and 100