SOLUTION: Alan has scored 78 , 93 , 63 , 81 , and 76 on his previous five tests. What score does he need on his next test so that his average (mean) is 79 ?

Question 1059467: Alan has scored
78
,
93
,
63
,
81
, and
76
on his previous five tests. What score does he need on his next test so that his average (mean) is
79
?
Found 3 solutions by jorel555, Alan3354, acw1213:
Answer by jorel555(1290)   (Show Source): You can put this solution on YOUR website!
So far, Alan has scored 78,93,63,81,&76 on his tests, giving him a grand total of 391 for 5 tests. To average 79 over 6 tests, he needs a grand total of 79x6, or 474 points. 474-391=83 points Alan needs to score to average a 79 over all his tests. ☺☺☺☺
Answer by Alan3354(69443)   (Show Source): You can put this solution on YOUR website!
Avg = (sum of elements)/(# of elements)

Answer by acw1213(28)   (Show Source): You can put this solution on YOUR website!
Remember the average formula.
You need to add up all scores of the tests and divide by the number of tests, 6.
This equation will equal his intended average, 79.
We know all test scores except the 6th score.
Let "x" represent the 6th score.
78 + 93 + 63 + 81 + 76 + x
--------------------------- = 79
6
Solve for "x" by first combining like terms.
Multiply by "6" on both sides.
Subtract the constant on both sides.
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