First, you need to convert the minutes into hours, to do this you divide the minutes by 60 (the amount of minutes in an hour). Once you've gotten the value (which is 2.5), you divide that by the amount of miles drove, then you get the unit rate, or in other words the kilometers per hour, which equals 49.6 km/h
By assuming the standard deviation of population 2.2 the confidence interval is 8.67 toys,8.94 toys.
Given sample size of 1492 children,99% confidence interval , sample mean of 8.8, population standard deviation=2.2.
This type of problems can be solved through z test and in z test we have to first find the z score and then p value from normal distribution table.
First we have to find the value of α which can be calculated as under:
α=(1-0.99)/2=0.005
p=1-0.005=0.995
corresponding z value will be 2.575 for p=0.995 .
Margin of error=z*x/d
where x is mean and d is standard deviation.
M=2.575*2.2/
=0.14
So the lower value will be x-M
=8.8-0.14
=8.66
=8.67 ( after rounding)
The upper value will be x+M
=8.8+0.14
=8.94
Hence the confidence interval will be 8.67 toys and 8.94 toys.
Learn more about z test at brainly.com/question/14453510
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Answer:
hi
Step-by-step explanation:
Answer:
false,true,false,true
Step-by-step explanation:
not 100% sure
hope it helped
:)