Question

a. the area under the normal curve between z is 84%. find z (enter a positive value).
b. the area under the normal curve to the left of z is 84%. find z.

Explanation:

Step1: Use z - table (standard normal table)

We know that the area under the standard - normal curve to the left of a z - value is given. We look up the value 0.84 in the body of the standard normal table.

Step2: Find the corresponding z - value

Looking up 0.84 in the standard normal table (the cumulative - distribution function of the standard normal distribution $\varPhi(z)$), we find that the z - value corresponding to an area of 0.84 to the left is approximately $z\approx1.00$.

Answer:

1.00