Question

In: Math

Q. 1. Suppose a population was normally distributed with a mean of 10 and a standard deviation...

Q. 1. Suppose a population was normally distributed with a mean of 10 and a standard deviation of 2. What proportion of the scores is below 12.5?

Q.2. Let’s say that the average IQ of a group of people is 105 with a standard deviation of 15. What is the standardized (or z- score) of someone:

(a) with an IQ of 93?

(b) with an IQ of 135?

No handwriting please, or make it clear

thanks

Expert Solution

q1)

z=x-u/s

p(x<12.5)=p(z<12.5-10/2)

=p(z<1.25) from z table

=0.8944

Q2)

WE KNOW THAT

a) with an IQ 93

Z=93-105/15

=-0.8

b) with an IQ 135

Z=135-105/15

=2

milcah answered 7 months ago

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