# Test 4 Score

Discussion in 'Basic Math' started by nycmathguy, Jul 3, 2022.

1. ### nycmathguy

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Let s = test 4 score

(88 + x)/2 = 90

Correct set up?

nycmathguy, Jul 3, 2022
2. ### MathLover1

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(88+88+88 + x)/4 = 90

(x + 264)/4 = 90
x + 264= 90*4
x = 360-264
x = 96 -> 4th test must be 96

MathLover1, Jul 3, 2022
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3. ### nycmathguy

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Your set up was my first choice.

nycmathguy, Jul 4, 2022
4. ### HallsofIvy

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The average of a list of numbers is the sum divided by the number of numbers in the list.
To find the average of these 4 numbers we must first add them. We want to find the fourth number so call that x,
We do not know the first 3 numbers but we know their average is 88 so we know their sum is 3(88)= 264. We want (264+ x)/4= 90. 264+ x= 4(90)= 360. x= 360- 264= 96.

HallsofIvy, Aug 16, 2022
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