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.
He saved 5/24 of his money
Make common denominators
1/6 * 4/4 =4/24
5/8 * 3/3= 15/24
15/24 + 4/24 = 19/24
24/24 - 19/24
= 5/24
Answer:
I believe it is X * 2 + 5 = Jim's total
Step-by-step explanation:
X is the amount of hours Kelly reads and multiplying X by 2 is how you find Tim's total. Then to find Jim's total you add 5 because that's how many more hours he reads than Tim.
Sound or vibration wave that is conducted
Answer: Ck.12.org
Step-by-step explanation: Just read the book
