Answer:
The sample size needed is 2401.
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 of the interval is:
95% confidence level
So 
, z is the value of Z that has a pvalue of 
, so 
.
Estimate the sample size needed if no estimate of p is available so that the confidence interval will have a margin of error of 0.02.
We have to find n, for which M = 0.02.
There is no estimate of p available, so we use 
The sample size needed is 2401.
First, find the simplified ratio of the given ratio:
Number of pirates: 22
Number of ships: 2
Divide 22 with 2 to find the ratio: 22/2 = 11
For every ship there is, there will be 11 pirates.
Now, find the ratio for the other questions:
IF there are 5 ships: 5 x 11 = 55
If there are 5 ships, there will be 55 pirates.
If there are 11 ships: 11 x 11 = 121
If there are 11 ships, there will be 121 pirates.
~
Answer: 3.64, 10.00
Step by step:
X=750+125.75x
subtract to variable (x) on one side
x-125.75x=750+125.75x-125.75x
-124.75x=750
divide -124.75 to get variable (x) by itself
-124.75x/-124.75=750/-124.75
x=-3000/499
or
x=-6 6/499
or
x=-6.01202
X = 32 because 100 / 4 is 25, which would make the numerator for x 32
