At most, Alana can spend $40 on carnival tickets. Ride tickets cost $4 each, and food tickets cost $2 each. Alana buys at least
16 tickets. The system of inequalities represents the number of ride tickets, r, and the number of food tickets, f, she buys. r + f ≥ 16
4r + 2f ≤ 40What is the maximum number of ride tickets she can buy?