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Chapter 6: Q. 21 (page 385)

Suppose x~N(8,9). What value of xis 0.67standard deviations to the left of the mean?

Short Answer

Expert verified

The value ofxis1.97

Step by step solution

01

Given Information

Given in the question that, X~N(8,9)

We have to find the value of xis 0.67standard deviations to the left of the mean.

02

Explanation 

According to the information, the value of zis -0.67

Here, localid="1649394314342" X~N(8,9)

Where, μ=8

σ=9

We can compute the value of zscore as follow:

z=x−μσ

Place the given value in the above equation.

−0.67=x−89

x−8=−0.67×9

x=−6.03+8

x=1.97

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Most popular questions from this chapter

Terri Vogel, an amateur motorcycle racer, averages 129.71seconds per 2.5mile lap (in a seven-lap race) with a standard deviation of 2.28seconds. The distribution of her race times is normally distributed. We are interested in one of her randomly selected laps.

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