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Chapter 6: Q 27. (page 373)

Running a mile A study of 12,000able-bodied male students at the University of Illinois found that their times for the mile run were approximately Normal with mean 7.11 minutes and standard deviation 0.74 minute. 7 Choose a student at random from this group and call his time for the mile Y. Find P(Y<6). Interpret this value.

Short Answer

Expert verified

The value ofP(Y<6)=6.68%

Step by step solution

01

Step 1. Given information.  

We have mean 7.11minutes and standard deviation 0.74minute.

02

Step 2. To find the value of  z. 

z=x-渭蟽z=6-7.110.74z鈮�-1.50

03

Step 3. To find the probability. 

P(Y<6)=P(Z<-1.50)=0.0668=6.68%

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