Question 310023
As thorough as Edwin's answer is you don't have time on a test to go through all of that. On a test, you want the quickest solution.
Of course Stan's method is the quickest.
So let's say you didn't know Stan's method (Edwin's method1)
We know we are going to lose time compared to method 1
It only involves a little multiplication and subtraction.
Quickly try 1 for n in each. We see it has to be negative 23
a)38-61=-23
b)61-24=positive so  move on.
c)61-84=-23
d) -46
so it is between a and c
try it for n=2 we need positive 38
76-61=15
122-84=38
that settles it
Answer is c