Question

In: Statistics and Probability

An IQ test has scores converted to Z scores. What % of people fall below a...

An IQ test has scores converted to Z scores. What % of people fall below a z = -2? Group of answer choices

2.28%

47.7%

97.7%

2%

Solutions

Expert Solution

Solution:

Given in the question

Z = -2

We need to calculate probability

P(Z<-2) = ?

Probability can be found from cumulative normal distribution table as follows:

P(Z<-2) = 0.0228 or 2.28%

So 2.28% people fall below Z = -2.


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