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

1 answer:

6 0

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

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