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.
Step by Step Answer:
10% of 460 = 46
46 x 9 =414
The Art Club sold 414 shirts.
Lines AB and AC are equal so you set up an equation like so...
4x + 1 = 2x + 23
Subtract 1 from both sides.
4x = 2x + 22
Subtract 2x from both sides.
2x = 22
Divide.
x = 11
Now you need to plug in 11 into 3x - 8.
3(11) - 8
= 33 - 8
= 25
So BC is 25.
I hope this helps love! :)
Answer:
40 apples
Step-by-step explanation:
4/7 of 70
1. rewrite in mathematical terms
4/7 * 70
2. solve
4/7 * 70
= 40