Answer:
The margin of error is multiplied by 1.41, which is 1 divided by the square root of 5.
Explanation:
The margin of error is:
![M = z*(\sigma)/(√(n))](https://img.qammunity.org/2021/formulas/mathematics/college/cvh8tdoppqkhyobio78yaazk1nqj1870w9.png)
In which z is related to the confidence level,
is the standard deviation of the population and n is the size of the sample.
The margin of error is inverse proportional to the square root of the sample size.
Then
Sample size n:
![M = z*(\sigma)/(√(n))](https://img.qammunity.org/2021/formulas/mathematics/college/cvh8tdoppqkhyobio78yaazk1nqj1870w9.png)
Modified(half the sample size):
![M_(M) = z*(\sigma)/(√(0.5n))](https://img.qammunity.org/2021/formulas/mathematics/high-school/4u5lujj5lsf60dxy7cocwllo6pnpx3n53p.png)
Ratio
![(M_(M))/(M) = (z*(\sigma)/(√(0.5n)))/(z*(\sigma)/(√(n))) = (√(n))/(√(0.5n)) = (√(n))/(√(0.5)*√(n)) = (1)/(√(0.5)) = 1.41](https://img.qammunity.org/2021/formulas/mathematics/high-school/gg6m2l7z6scz1cb3mehm2trptpszwdy9bm.png)
The margin of error is multiplied by 1.41, which is 1 divided by the square root of 5.