Answer
The 30th percentile for the number of chocolate chips in an 18-ounce bag of Chips Ahoy is 1201 chips.
Work Step by Step
$\mu$ =1262, $\sigma$ = 118
i ) z- score corresponding to an area of 0.30
ii) Sub $\sigma = 118 , \mu= 1262, z = -0.52$ into z = $\frac{x - \mu}{\sigma}$ and solve for x:
z = $\frac{x - \mu}{\sigma}$
$x$ = $\mu$ + $z\sigma$
$x$ = $1262 + (-0.52 \times 118)$
$x$ = $1200.64$
$x$ $\approx$ 1201
