Answer:
We need a sample size of least 119
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
.
Sample size needed
At least n, in which n is found when 
We don't know the proportion, so we use
, which is when we would need the largest sample size.






Rounding up
We need a sample size of least 119
Answer:
It might be B
Step-by-step explanation:
6 boxes of spaghettis for 20 persons so that means 12 boxes for 40 persons since there are 50 persons we have 10 persons left since 10 is equals to 20 divided by 2, divide 6 by 2 which is equals to 3 then add 12
Answer: 15
Answer:
x = 40
Step-by-step explanation:
50 + 150 + 2x + x + x
200 + 4x
360 - 200 = 160
160 / 4 = 40
x = 40
50 + 80 + 40 + 150 + 40