Question

If the mean of five observation $x,x+2,x+4,x+6$ and $x+8$ is $13$, then find the value of $x$.

Answer 1

Given that the mean of five observation $x,x+2,x+4,x+6$ and $x+8$ is $13$.

we know that

$mean=\frac{sumofobservations}{numberofobservations}$

$\Rightarrow 13=\frac{x+(x+2)+(x+4)+(x+6)+(x+8)}{5}$

$13=\frac{5x+20}{5}$

$13=\frac{5(x+4)}{5}$

$13=x+4$

$x+4=13$ value of $x=9$

$x=13-4$

$x=9$