Question

The mean of five numbers is 15. four of the numbers are 3,19,8, and 32 whats the fifth number

Answer 1

Setup Average Equation:
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Average=Sum of our 4 numbers + unknown number of x
                ____________________________________
                                          Total Numbers
15 = 3 + 19 + 8 + 32 + x
       ______________
                      5
Cross Multiply
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3 + 19 + 8 + 32 +  = 15 x 5
x + 62 = 75
Subtract 62 from both sides of the equation to isolate x:
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x + 62 - 62 = 75 - 62
x = 13