SOLUTION: Justin has an average of 94 in math, based on five test scores. He needs a 93 average to get an "A". What grade must he get on his last test in order to get an "A"? Round to the

Algebra ->  Algebra  -> Average -> SOLUTION: Justin has an average of 94 in math, based on five test scores. He needs a 93 average to get an "A". What grade must he get on his last test in order to get an "A"? Round to the      Log On

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Question 391180: Justin has an average of 94 in math, based on five test scores. He needs a 93 average to get an "A". What grade must he get on his last test in order to get an "A"? Round to the nearest whole number, if necessary.
Answer by josmiceli(9680) About Me  (Show Source):
You can put this solution on YOUR website!
Let x = the grade he must get on last test
The sum of his scores on the 1st 5 tests is 5%2A94+=+470
because the formula for average is (sum of scores)/(# of tests) = average
%28470+%2B+x%29%2F6+=+93
470+%2B+x+=+6%2A93
x+=+558+-+470
x+=+88
He must get at least an 88
check:
suppose he got an 87?
%28470+%2B+x%29%2F6+=+93
%28470+%2B+87%29%2F6+=+93
557%2F6+=+92.83
He wouldn't get an A