SOLUTION: What value of x makes the mean of the first three numbers in the list equal to the mean of the last four numbers? 15 5 x 7 9 17

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Question 799290: What value of x makes the mean of the first three numbers in the list equal to the mean of the last four numbers?
15 5 x 7 9 17

Answer by ankor@dixie-net.com(22740)   (Show Source): You can put this solution on YOUR website!
What value of x makes the mean of the first three numbers in the list equal to the mean of the last four numbers?
15 5 x 7 9 17
=
4(20+x) = 3(x+33)
80 + 4x = 3x + 99
4x - 3x = 99 - 80
x = 19
;
You can confirm this for yourself

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