Answer:
A sample of 1068 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:

95% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
At 95% confidence, how large a sample should be taken to obtain a margin of error of 0.03 for the estimation of a population proportion?
We need a sample of n.
n is found when M = 0.03.
We have no prior estimate of
, so we use the worst case scenario, which is 
Then






Rounding up
A sample of 1068 is needed.
Answer:
1332 i think
Step-by-step explanation:
287+379=666
666*2=1332
Given cos theta is equal to - 4/ 7 then we can conclude that theta is in the second and third quadrants. In this case, the other leg is equal to square root of (7^2 - 4^2 ) equal to square root of 33. In this case, sin theta can be equal to +- square root of 33 / 7 and tan theta is equal to +-square root of 33 / 4.