silvia's test scores are 86,81 and 92 what must she score on her fourth test in order to have an average of 90 for all four test

Question

Marina CMI [18]

3 years ago

7

silvia's test scores are 86,81 and 92 what must she score on her fourth test in order to have an average of 90 for all four test

s

Mathematics

2 answers:

lianna [129] · Answer 1 · 2022-05-24T20:38:39+03:00

lianna [129]3 years ago

8 0

90 * 4 = 360 (total of 4 tests for average of 90)

86 + 81 + 82 = 259 (total first 3 tests)

360 - 259 = 101

answer:
In order to have an average of 90, she must score 101 on her 4th test.

belka [17] · Answer 2 · 2022-05-24T19:22:31+03:00

belka [17]3 years ago

7 0

Silvia has to score a 101 to get an average of 90 for all four tests.
Explanation: 90=(86+81+92+x)/4
360=259+x
101=x