<PRE><B>Question 928157</B>
x = score he needs on the fourth test
y = sum of scores of the first three tests
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y/3 = 88
y = 3*88
y = 264
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(264 + x)/4 = 90
264 + x = 90*4
x = 90*4 - 264
x = 96
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answer:
x = score he needs on the fourth test = 96
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