AP questions

If first term is -11 and common differebce is 20

1. what is the 2nd term
2. what is the 3rd term
3. what is the fourth term
4. what is the 10th term
5. if last term is 179, how many terms are there?

2. If a = -11 and last term is 79 and the sum of all the terms are 340, what is the sum of terms?

Sum of terms = n/2 (first + last), so right away n number of terms can be found.

then common difference d can be found since last term = first + (n - 1) d