Question

The heights of students in a 5^{th} grade class are
normally distributed with mean height 45 inches and standard
deviation 5 inches. The students are divided into groups of 3. What
height is such that the probability that the total height for a
given group exceeds that height is 5%?

Answer #1

Solution :

_{}
= 45

_{}
=
/
n = 5 /
3

P(Z > 1.645) = 0.05

z = 1.645

= z *
_{}+
_{}
= 1.645 * 5 /
3 + 45 = 49.75

Height = 49.75 inches

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ANSWER 0.0018
please show step by step ! thank you

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