Answer:
We need a sample size of at least 383.
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:

85% 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 85% confidence level with an error of at most 0.03
We need a sample size of at least n.
n is found with 
Then






Rounding up
We need a sample size of at least 383.
Answer:
a=16400 feet
Step-by-step explanation:
t = -0.0035 a +g
-17.40 = -0.0035 a+40
-17.40-40=-0.0035a+40-40
-57.40=-0.0035a
a = -57.40/-0.0035
a=16400 feet
Answer:
30x+12
Step-by-step explanation:
distribute 6 into (2x+1) and 3 into (6x+2) basically multiply
12x+6+18x+6
combine like terms
12x+18x=30x
6+6=18
hope this helps
4x + 30 = 5x + 20
30 - 20 = 5x - 4x
10 = x <==