Subtracting a number is the same as adding its opposite. Use this understanding to complete each of the equations below.

Enter numbers to evaluate ‐9−(‐12).

‐9−(‐12)= ‐9 + =

Enter numbers to evaluate ‐9−12.

‐9−12= ‐9 + ? =

Now, martin can reasonably guess that the standard deviation for the entire population of people at the mall during the time of the survey is $1.50. what is the 95% confidence interval about the sample mean? interpret what this means in the context of the situation where 95 people were surveyed and the sample mean is $8. use the information in this resource to construct the confidence interval.