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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-μσz=6-7.110.74z≈-1.50

03

Step 3. To find the probability. 

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

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Most popular questions from this chapter

Toothpaste Ken is traveling for his business. He has a new 0.85-ounce tube of toothpaste that’s supposed to last him the whole trip. The amount of toothpaste Ken squeezes out of the tube each time he brushes is independent, and can be modeled by a Normal distribution with mean 0.13 ounce and standard deviation 0.02 ounce. If Ken brushes his teeth six times on a randomly selected trip, what’s the probability that he’ll use all the toothpaste in the tube?

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Toothpaste Ken is traveling for his business. He has a new 0.85-ounce tube of toothpaste that's supposed to last him the whole trip. The amount of toothpaste Ken squeezes out of the tube each time he brushes varies according to a Normal distribution with mean 0.13ounces and standard deviation 0.02ounces. If Ken brushes his teeth six times during the trip, what's the probability that he'll use all the toothpaste in the tube? Follow the four-step process.
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