You can add the numbers together so:
12.6
3.1
<u>+ 5.4
</u> 21.1
<u>
</u>Since the sum of the numbers is 21.1, it is greater than 20<u>
</u>
<span>3.9375 hope I helped :)</span>
Answer:
Area of regular pentagon is 238.95 square inches.
Step-by-step explanation:
Given a regular pentagon with side length of 11.8 inches and dotted line from center to middle of side of 8.1 inches.
we know a regular polygon divides into 5 congruent triangles.
Side of pentagon i.e base of one triangle is 11.8 inches.
Also, distance from center to middle of side which is height of triangle is 8.1 inches.
Area of 1 triangle= 
= 
= 47.79 sq inches.
Area of regular pentagon=area of 5 congruent triangles=
=238.95 sq inches.
Using the z-distribution, it is found that she should take a sample of 46 students.
<h3>What is a z-distribution confidence interval?</h3>
The confidence interval is:

The margin of error is:

In which:
is the sample mean.
is the standard deviation for the population.
In this problem, we have a 95% confidence level, hence
, z is the value of Z that has a p-value of
, so the critical value is z = 1.96.
Scores on the math portion of the SAT are believed to be normally distributed and range from 200 to 800, hence, by the Empirical Rule the standard deviation is found as follows:



The sample size is n when M = 29, hence:





n = 45.67.
Rounding up, a sample of 46 students should be taken.
More can be learned about the z-distribution at brainly.com/question/25890103
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