Is it possible to use the formula for an arithmetic sequence to solve this, substituting 1 for a, 1 for d, and 20 for n for series u and 21 for a, 1 for d, and 40 for n for series v? Thank you for your help!

Kayla, you have to show me your work in order for me to say it is possible or not. In tests like this, rarely do you have to depend on formulas. For example, here you see the answer choices are pretty spread out, which indicates it is a good idea to use estimation.

The sum of integers from 1 to 20 can be estimated this way: 1 + 20, 2 + 19, 3 +18, etc. which adds up to 21 times 10 (since there are about 10 pairs), or about 200.

The sum of integers from 21 to 40 can be estimated as the sum of: 21 + 40, 22+39, ... or about 61 times 10, or about 600.

So the difference between the two sums are about 400, and there is only 1 answer which is close to (in this case the same to) our estimate.

Yes it's possible to use AP for getting the sums of the two series

Yes it's possible to use AP for getting the sums of the two series

I need a little more explanation please.Thank you.I calculated it to get the right answer but It took time.