Answer:
The 85% confidence interval for the mean number of toys purchased each year is (6.7, 6.9).
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 .
That is z with a pvalue of , so Z = 1.44.
Now, find the margin of error M as such
In which is the standard deviation of the population and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 6.8 - 0.1 = 6.7
The upper end of the interval is the sample mean added to M. So it is 6.8 + 0.1 = 6.9
The 85% confidence interval for the mean number of toys purchased each year is (6.7, 6.9).
Answer:
Step-by-step explanation:
we need a 4-digit number from the numbers (without repetition ).
possible number at thousand place
Possible numbers at hundred place
Possible numbers at place
possible number at unit place
<em>So total possible numbers</em>
<u>Other method :</u>
We are taking numbers out of and here order matters so we will use permutation.
Total possible numbers
Answer:
2: option four
3: option four
Step-by-step explanation:
they are both option four
Answer:
5x-10
Step-by-step explanation:
Answer:
33.53
Step-by-step explanation:
OB is a radius of the circle, and OC is also a radius of the circle, so both are equal length. That makes ΔOBC an isosceles triangle.
If we cut ΔOBC in half, the angle formed is 125° / 2 = 62.5°.
Therefore:
sin 62.5 = (x/2) / 18.9
x = 37.8 sin 62.5
x ≈ 33.53