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.
Answer: I would say the third one
Step-by-step explanation: I hope this helps if it is wrong i am so sorry I hope you have a great day of night stay safe :)
1) 3/12
Because 1/3 would have changed to 4/12,
1x4= 4
3x4=12
You need to multiply them by the same number and 1) was multiplied by three on the numerator and four on the denominator.
To make calculation easier, we first multiply
1.35 × 100 = 135
then we need to find how many groups of 5 are there in 135.
to do so, we simply take
135 ÷ 5 = 27
therefore, the answer is <u>27.</u>
Answer:
the regular price was 33.75