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
#SPJ4
Answer:
Step-by-step explanation:M+F=39
M+F=39
F=M-9
Substitute
M + M - 9 = 39
2M = 48
M=48/2
M=24
24+F=39
F=39-24=15
F=15, M=24
Answer:
The critical value for the 95% confidence interval is z = 1.96.
Step-by-step explanation:
We have that to find our 
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of 
So it is z with a pvalue of 
, so z = 1.96.
The critical value for the 95% confidence interval is z = 1.96.
Answer:
1/3 + 1/4 = 4/12 + 3/12 = 7/12
7/12 = both brothers ate 7 crackers out of 12 crackers
there were 5 crackers left on the plate means 5/12 crackers left on the plate
answer: 12 crackers at the beginning
Step-by-step explanation:
Answer:
<h3>dn = -7^n-1</h3>
Step-by-step explanation:
Given the sequence -1,-7,-49,-343,....
We are to find the nth term of the sequence
dn = ar^n-1
a is the first term = -1
r is the common ration = -7/-1 = -49/-7 = 7
n is the number of terms
Substitute
dn = -1(7)^n-1
dn = -7^n-1
hence the nth term of the sequence is dn = -7^n-1
