Question

given a population of 2000 normally distributed stores with mean equal to 74, and a standard deviation of 6. How many scores are between 50 and 70?

Answer 1

$$n=2000, \mu=74,\sigma=6,Z=\frac{(x-μ)}{σ}$$ $$P(50<X<70)=P(Z<\frac{70-74}{6})$$

$$-P(Z\le\frac{50-74}{6})$$

$$=0.25249-0.00003$$

$$=0.25246$$

$0.25246(2000)=505$

$505$ scores