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The traffic commissioner wants to know the average speed of all vehicles driving on River Rd....

The traffic commissioner wants to know the average speed of all vehicles driving on River Rd. Police use radar to observe the speeds for a sample of 20 vehicles on River Rd.

For the vehicles in the sample, the average speed is 31.3 miles per hour with standard deviation 7.0 mph.

Construct and interpret a 98% confidence interval estimate of the true population average speed of all vehicles on River Rd. Use a 98% confidence level.

X = ________________________________________________________________________

population parameter:  = ________________________________________________________________

random variable X = ____________________________________________________________________ We are

Math   Statistics-And-Probability   
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Conclusion:- we are 98% confidence that population average speed of all vehicles on River Rd is between 9.3258 to 17.2742.

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