Question

1. Every Normal model is defined by its parameters, the mean and the standard deviation. For each model described here, find the missing parameter. As always, start by drawing a picture.

   1. μ=20, 45% above 30, σ= ?

   2. μ=88, 2% below 50, σ= ?

   3. σ=5, 80% below 100, μ=?

   4. σ=15.6, 10% above 17.2, μ=?

Answer 1

z table for P(z<Z) :

solution :

P.S. (please upvote if you find the answer satisfactory)