Answer
a. From the given normal distribution, μ=15 and σ= 2.4.
$P(x \gt 20)$ = $P(z \gt \frac{20-15}{2.4} )$
= $P( z \gt 2.0833)$
=0.0186
b. $P(x \gt 25)$ = $P(z \gt \frac{25-15}{2.4} )$
=$P( z \gt 4.167)$
=0
It's not possible since the probability of $P(x \gt 25)$ is 0.
Work Step by Step
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