Question

If the Census wants to increase its level of confidence and keep the error bound the same by taking another survey, what changes should it make?

Short answer

If the Census wants to increase its level of confidence and keep the error bound the same by taking another survey, than they should increase the sample size $n$.

Step-by-step solution

Given Information

The sample mean is $8.2$minutes. There is a known standard deviation of $2.2$ minutes. The population distribution is assumed to be normal.

Explanation

A tighter confidence interval with a smaller margin of error will arise from a bigger sample size or lower variability. A wider confidence interval with a larger margin of error will arise from a smaller sample size or higher variability.