You decide to increase your Utah county coronavirus sample to 10 counties and estimate the same sample standard deviation you did with your sample of 5 counties. This will the margin of error associated with your 90% confidence interval.

This will decrease the margin of error associated with your 90% confidence interval.

Step-by-step explanation:

Margin of error:

The margin of error of a confidence interval is given by a formula that follows the following format:

In which z is related to the confidence level, s is related to the standard deviation and n is related to the size of sample.

From the formula:

M and n are inversely proportional, which means that if the sample size is increased, the margin of error decreases.

In this question:

Sample size increases from 5 to 10, so the margin of error decreases.

answer: 204

step-by-step explanation:

we are told that the revenue is

x⋅(4080−10x)=−10x^2+4080x

this is a quadratic function, so to maximize it we should find the x-value of its vertex. recall that the x-value of the vertex of the parabola ax^2+bx+c is given by the formula −b/2a.

so in this case, we have a=−10 and b=4080, so the x-value of the vertex is

−b/2a= −(4080)/2(−10)=204