Answer
$P(x < 1500) = 0.1894$
Work Step by Step
$\mu$ = 1550, $\sigma$ = 57
Want to find $P( x < 1500 )$
i) Convert 1500 to a z-score:
z = $\frac{x - \mu}{\sigma}$
z = $\frac{1500 - 1550}{57}$
z= -0.88
ii) $P(x < 1500) = P(z < -0.88) = 0.1894$
