Algebra 2 Problem, Combinations/Permutations

Question

I'm having trouble figuring out how to start this problem, and why my answer is always incorrect. I keep getting 435, but I am marked wrong. Please help! Here's the problem:

In an economics class with 30 students, the teacher wants 2 different students to answer problems 4 and 9 in front of the class. In how many ways can the teacher pick students for the problems?

a. 870

b. 435

c. 560

d. 660

Answer 1

Hello, Camille.

Teacher have 30 different students to answer for question #4 also

Teacher have 29 different students to answer for question #9

Since they are separated possibility; just multiply

30*29 = 870

Hope that helps