Answer:
Your answer is 15, 100% of the exam is 15 questions.
Step-by-step explanation:
60% x ? = 9
We need to do 9 divided by 60%
Which is actually 9 divided by 60/100.
Which is equal to; (100 x 9) divided by 6.
Which is then 900 divided by 60 which equals 15.
Answer: 15
I'm not sure what your trying to ask is that the full question
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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The founded number should be 9,000