ANSWER:
103.4
STEP-BY-STEP EXPLANATION:
Given:
Standard deviation (σ) = 17
x = 100
The probability is 42%, that is 0.42, we look for this value in the normal table to determine the value of z as follows:
z = -0.2
Knowing that value we can calculate the mean, just like this:
[tex]\begin{gathered} z=\frac{x-\mu}{\sigma} \\ \\ \text{ We replacing:} \\ \\ -0.2=\frac{100-\mu}{17} \\ \\ 100-\mu=-0.2\cdot17 \\ \\ \mu=100+0.2\cdot17 \\ \\ μ=103.4 \end{gathered}[/tex]The mean is equal to 103.4
