SOLUTION: the average of four numbers is 638.4 the first three numbers are 216,159.8,301.25. what is the fourth number?

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Question 507010: the average of four numbers is 638.4 the first three numbers are 216,159.8,301.25. what is the fourth number?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
the average of four numbers is 638.4 the first three numbers are 216,159.8,301.25. what is the fourth number?
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Let the 4th number be "x":
(216+159.8+301.25 + x)/4 = 638.4
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677.05 + x = 4*638.4
x = 1876.55
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Cheers,
Stan H.