Question

The arithmetic mean of 6,7,8,(x+3) and 2 is 5. then x is

Answer 1

Mean = (6+7+8+x+3 +2) ÷5=(26+x)÷5
ATQ..
(26+x)÷5=5
26+x=5×5
x=25-26
x=-1

Answer 2

$mean \: = \: \frac{sum \: of \: all \: numbers}{total \: numbers} \\ 5 \: = \: \frac{6 \: + \: 7 \: + \: 8 \: + \: x \: + \: 3 \: + \: 2}{5} \\ 25 \: = \: 26 \: + \: x \\ x \: = \: 25 \: - 26 \\ x \: = \: - 1$