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 84 and 74

Answer 1

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

$P(74<X<84)=P(\frac{74-74}{6}<Z<\frac{84-74}{6})$

$=P(0<Z<1.67)=P(Z<1.67)-P(z<0)$

$=0.9525-0.500$

$=0.4525$

$=0.4525*2000$

$=905$ stores