Answer:
A = 201 cm²
Step-by-step explanation:
We know that the area of a circle can be calculated with the formula:
A = πr² = π(d/2)²
with d being the diameter.
Therefore:
A = 3.14(8cm)² = 201 cm²
You may recognize that ∆WYZ is a 3-4-5 right triangle. Without any work, then
c = 5
_____
If you don't remember that a right triangle with legs 3 and 4 has a hypotenuse of 5, you can compute it using the Pythagorean theorem.
c² = 3² + 4²
c² = 9 + 16 = 25
c = √25 = 5
The margin of error of the random selection is 0.29
The given parameters are:
--- the sample size
--- the standard deviation
--- the mean
--- the confidence level.
The margin of error (E) is calculated as follows:

So, we have:


The z-value for 90% confidence level is 1.645.
Substitute 1.645 for z


Take square roots

Multiply

Approximate

Hence, the margin of error is 0.29
Read more about margin of error at:
brainly.com/question/14396648
Answer:In statistics, a forecast error is the difference between the actual or real and the predicted or forecast value of a time series
Step-by-step explanation:find the Mean Absolute Percent Error (MAPE) of your forecast. Statistically MAPE is defined as the average of percentage errors.