Using the z-distribution, a sample size of 180 is needed for the estimate.
<h3>What is a z-distribution confidence interval?</h3>
The confidence interval is:

The margin of error is given by:

In which:
is the sample mean.
is the standard deviation for the population.
In this problem, we have a 98% confidence level, hence
, z is the value of Z that has a p-value of
, so the critical value is z = 2.327.
The population standard deviation is of
, and to find the sample size, we have to solve for n when M = 4.
Hence:





n = 179.03.
Rounding up, as a sample size of 179 would result in an error slightly above 4, a sample of 180 is needed.
More can be learned about the z-distribution at brainly.com/question/25890103
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Answer:
90.31 is greater than 90.302
Step-by-step explanation:
Answer:
- Collect like terms and simplify
- Subtract 7 from both sides
Step-by-step explanation:
METHOD 1

METHOD 2

Answer:
Try 458.96 (round if needed)
Step-by-step explanation:
First you find the volume of the cone. (pi*radius^2*h/3)
Then you find the volume of a cylinder. (pi*radius^2*h) add these two up.
You would have to subtract 12.5 and 8.5 to get the height of the cone.
Also you would have to subtract 6 inches off of your total.
(Sorry If this explanation sucked.)
Answer:
C
Step-by-step explanation:
The formula for the area of a trapezoid is:
(height)(sum of parallel lines)
Thus, the formula in this question would be:
(4)(4+8) which is option C