Question

Given that is a standard normal random variable, find for each situation (to 2 or 3 decimals).

a. The area to the left of z is 0.8

b. The area to the left of z is 0.981

c. The area to the right of z is 0.6045

d. The area between -z and z is 0.82

(Hint: Enter the positive z-value)

Answer 1

Hello Sir/ Mam

(a)

Using excel function, "=NORM.S.INV(0.8)", we get z-score= 0.8416

(b)

Using excel function, "=NORM.S.INV(0.981)", we get z-score = 2.0749

(c)

Using excel function, "=NORM.S.INV(1-0.6045)", we get z-score = -0.2650

(d)

Using excel function, "=NORM.S.INV(0.09)" and "=NORM.S.INV(0.91), we get z-scores -1.3408 and 1.3408 respectively.

I hope this solves your doubt.

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