question: Imma has 3 cats. She feeds her cats twice a day with 60 grams of cat food. How many days will 720 grams of cat food last?
answer: The 3 cats consume 60 grams/cat x 3 cats = <<60*3=180>>180 grams of food per meal.
  Since they eat twice a day, then they consume 180 grams/meal x 2 meals/day = <<180*2=360>>360 grams in a day.
  So, 720 grams of cat food only last for 720 grams / 360 grams/day = <<720/360=2>>2 days.
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