From the statement we know that the cheetah can reach a speed of 70 mph, but it can be maintained for no more than 1,640 feet.
The expression "no more than" means that at least it can be reached but never exceeded, it involves that the distance can be less or equal than 1,640 feet but never more than that.
Idk what it has to do with simplifying but what I would do is multiply 1 times 3. That gives u 3. Then add Ben's one hour and Brooke's 3 hours together. That gives u 4 hours total.