Question

A 35 pound dog eats an average of 2 1/2 cups of dry dog food a day. If you assume that there is a relationship between size and consumption, the amount of food an animal eats, how much food does a 70 pound dog eats? if your dog is 140 pounds, and you have 7 1/2 cups of food, do you have enough? explain your answer. Challenge: An 8 pound cat eats an average of 1/2 cup of dry food. Per pound, which type of animal eats more, cat or a dog? Explain your answer.

Answer 1

70 / 35 = 2
So the 70 pound dog weights double the weight of the 35 pound dog, so he will eat twice as much.

2 x 2.5 = 5 cups

Meaning he will eat 5 cups of dry dog food a day.

By the same logic a 140 pound dog would have to eat twice what a 70 pound dog eats, that is 10 cups of dry dog food a day, so 7 1/2 cups are not enough.

Challenge: per pound a dog eats more than a cat. Since you know a 140 pound dog eats 10 cups, you can dive 140 by 10, to find out that each cup feeds 14 pounds, so half a cup would be the amount of food to feed a 7 pound dog, meaning that a dog weighing 1 pound less than a 8 pound cat would need the same amount of food, so it eats more than a cat.