18 would be the right answer
Answer:
A sample of 499 is needed.
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 is given by:

In this question, we have that:

90% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
How large a sample would be required in order to estimate the fraction of tenth graders reading at or below the eighth grade level at the 90% confidence level with an error of at most 0.03
We need a sample of n, which is found when
. So






Rounding up
A sample of 499 is needed.
343in3 is the answer to this math question
Since we need your monthly bill we will call it the variable B for now, (Unless you have the bill, if so replace it with the variable)
Multiply 1.64 x B since the exchange rate is different than the US bill,
For example, say your bill is $100 in the U.S.
You do 1.64 x 100 = A monthly bill of $164 if you lived in Britain
Answer: 72/20 = <u>3 3/5</u>
Step-by-step explanation:
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