Question 666246
x = score needed on 4th test 
{{{(87+84+85+x)/4 = 90}}}
Solve for x
{{{(256 + x)/4 = 90}}}
...
Multiply both sides by 4
256 + x = 360
x = 360 - 256
{{{highlight_green(x = 104)}}}
Only with bonus points!
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