a judging panel will have 6 members chosen from 8 teachers and 10 students. there must be at least 3 students on the panel. in how many ways could there be

Question

a) 3 students on the panel
b) 4 students on the panel

im not sure where to go on this one because from my understanding so far, the way to go about this would be (10C3) + (8C3) for A) at least

Answer 1

I believe you want 10C3 * 8C3, not +
B is similar