Answer
$x$ = $47.90$
Work Step by Step
i ) z score corresponding to the 38th percentile (area of 0.38) = -0.3
ii) Sub $\sigma = 7 , \mu= 50, z = -0.3$ into z = $\frac{x - \mu}{\sigma}$ and solve for x:
z = $\frac{x - \mu}{\sigma}$
$x$ = $\mu$ + $z\sigma$
$x$ = $50 + (-0.3 \times 7)$
$x$ = $47.90$
