Question

X has a normal distribution with the given mean and standard deviation. Find the indicated probability. (Round your answer to four decimal places.)

μ = 36, σ = 20, find P(35 ≤ X ≤ 48)

Answer 1

P(35 ≤ X ≤ 48)

$=P\left ( \frac{35-36}{20}\leq Z\leq \frac{48-36}{20} \right )$

$=P\left ( -0.05\leq Z\leq 0.6 \right )$

$=P[Z\leq 0.6]-P[Z\leq -0.05]$

=0.7257-0.4801...........................by using normal probability table.

=0.2457