Question

Suppose 2 is a normally distributed random variable with I = 12 and o= 3Note: Enter your answers as a percent (for example, 74.22 not 0.7422).

Answer 1

a)

We want the find P(x < 13)

We would calculate the z score by applying the formula,

z = (x - μ)/σ

From the information given,

μ = 12

σ = 3

x = 13

Thus,

z = (13 - 12)/3

z = 0.33

P(x < 13) is the area to the left of z = 0.33 on the normal distribition table. From the table,

P(x < 13) = 0.6293

We would convert it to percentage by multiplying by 100. Thus,

P(x < 13) = 62.93%