document.write( "Question 785660: A student has scores of 86.5, 87, and 91.5 on his first three tests. He needs an average of at least 90 to earn a grade of A. What is the minimum score that the student needs on the fourth test to ensure a A? \n" ); document.write( "
Algebra.Com's Answer #477660 by xinxin(76)\"\" \"About 
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Suppose he needs to get a minimum score of X, then
\n" ); document.write( "(86.5+87+91.5+X)/4=90
\n" ); document.write( "X=360-86.5-87-91.5=95\r
\n" ); document.write( "\n" ); document.write( "He needs the score of 95 to ensure a A.
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