Question

Consider the normal curve. (Give your answers correct to four decimal places.)

(a) Find the area to the right of z = 0.00.

(b) Find the area to the right of z = 1.28.

(c) Find the area to the right of z = -1.67.

(d) Find the area to the left of z = 1.46.

(e) Find the area to the left of z = -1.46.

Answer 1

a) We have to find the area to the right of z = 0.00.

That is we have to find P(Z > 0.00)

P(Z > 0.00) = 0.5

b) We have to find the area to the right of z = 1.28.

That is we have to find P(Z > 1.28)

P(Z > 1.28) = 1 - P(Z < 1.28) = 1 - 0.8997 = 0.1013 ( Using z table)

c) We have to find the area to the right of z = -1.67.

That is we to find P(Z > - 1.67)

P(Z > - 1.67) = 1 - P(Z < - 1.67) = 1 - 0.0475 = 0.9525 ( Using z table)

d) We have to find the area to the left of z = 1.46.

That is we have to find P(Z < 1.46)

P(Z < 1.46) = 0.9279 ( Using z table)

e) We have to find the area to the left of z = -1.46.

That is we to find P(Z < - 1.46)

P(Z < - 1.46) = 0.0721