<PRE><B>Question 526739</B>
Let
Elise must score = x



Average = some of quantities /  number of quantities
90=(84+96+88+x)/4
90=(268+x)/4
Multiply by 4 both sides
90*4=4*(268+x)/4
360=268+x
360-268=x
92=x
x=92

Elise must score 92 to get an average of 90


Check
=====
Average = some of quantities /  number of quantities
Average = (84+96+88+92)/4
Average = 360/4
Average = 90


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