SOLUTION: the average of 3 numbers is 27. If a 4th number is added the new average is 22. What number was added?

Algebra ->  Average -> SOLUTION: the average of 3 numbers is 27. If a 4th number is added the new average is 22. What number was added?      Log On


   



Question 832902: the average of 3 numbers is 27. If a 4th number is added the new average is 22. What number was added?
Found 2 solutions by JulietG, stanbon:
Answer by JulietG(1812) About Me  (Show Source):
You can put this solution on YOUR website!
27 + 27 + 27 + x = 4*22
81 + x = 88
Subtract 81 from each side
x = 7

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
the average of 3 numbers is 27. If a 4th number is added the new average is 22. What number was added?
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Equations:
(a+b+c)/3 = 27
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(a + b + c + x)/4 = 22
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From the 1st equation, a+b+c = 3*27 = 81
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Substitute into the 2nd equation and solve for "x":
(81+x)/4 = 22
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81+x = 88
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x = 7
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Cheers,
Stan H.
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