Answers

2016-07-03T22:17:01+08:00
Arithmetic mean is just the terms added together and dived by the number of terms. Therefore:
((x+2) + (4x+5))/2 = 3x+2
x+2+4x+5 = 6x+4
5x + 7 = 6x + 4
x = 3

Check:
3 + 2 = 5
4(3) + 5 = 17
3(3) + 2 = 11

(5+17)/2 = 22/2 = 11
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