Answer:
6 movies = 1st plan
7 movies = 1st plan
8 movies = Either is fine. (They're the same price)
9 movies = 2nd plan
10 movies = 2nd plan
Explanation:
6 movies (1st plan) = 20 + 5 × 6
= 50 (less than 60 so it is cheaper)
7 movies (1st plan) = 20 + 5 × 7
= 55 (less than 60 so it is cheaper)
8 movies (1st plan) = 20 + 5 × 8
= 60 (same as 2nd plan so either is fine)
9 movies (1st plan) = 20 + 5 × 9
= 65 (more than 60 so 2nd plan is better)
10 movies (1st plan) = 20 + 5 × 10
= 70 (more than 60 so 2nd plan is better)