Because 3 2/4 would be the answer when you subtract it and most teachers and/or tests want you to simplify the answer which would be 1/2 because you would divide the numerator and denominator by 2.
Answer:
The 98% confidence interval for the true difference between testing averages for students using Method 1 and students using Method 2 is (-8.04, 0.84).
Step-by-step explanation:
The (1 - <em>α</em>)% confidence interval for the difference between population means is:

The information provided is as follows:

The critical value of <em>z</em> for 98% confidence level is,

Compute the 98% confidence interval for the true difference between testing averages for students using Method 1 and students using Method 2 as follows:


Thus, the 98% confidence interval for the true difference between testing averages for students using Method 1 and students using Method 2 is (-8.04, 0.84).
answer is either A or D
I hope this help. but I'm not really sure.