Answer:
A. 2πr
Step-by-step explanation:
Equilateral triangle are also equiangular which means all angles are 60 degrees. thus our needed altitude is the leg of a right triangle with other leg 4 and hypotenuse 8. 4² +a² = 8²
a² = 48
a=√48 = 4√3
Answer:
a. .92
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
.
The margin of error of the interval is:

The lower bound is the point estimate
subtracted by the margin of error.
The upper bound is the point estimate
added to the margin of error.
Point estimate:
The confidence interval is symmetric, so it is the mean between the two bounds.
In this problem:

Sample of 400, which means that 
Margin of error is the estimate subtracted by the lower bound. So 
We have to find z.




has a pvalue of 0.96.
This means that:




Confidence level:

So the correct answer is:
a. .92
Answer:
|x - 4| ≤ 0.3
Step-by-step explanation:
The actual width = 4
Maximum variation, x = 0.3
Hence, the lowest width position based on actual width and possible variation is :
4 - 0.3 ≤ x ≤ 4 + 0.3
3.7 ≤ x ≤ 4.3
9514 1404 393
Answer:
24 m
Step-by-step explanation:
The area formula tells us ...
22 = xy . . . . . square meters
Adding twice this to the quadratic constraint gives ...
(x^2 +y^2) +2(xy) = (100) +2(22)
(x +y)^2 = 144
x +y = √144 = 12
The perimeter is double this amount, so is ...
P = 2(x +y) = 2(12) = 24 . . . . meters