A bag of rice weighs 80oz. If a serving of rice is 2 oz, how much rice will be left after you prepare 10 servings? Explain why you choose the method you used.

Answer 1

If each serving of rice is 2 ounces, and you need ten servings, it is a multiplication that gives:

(2 oz)*(10) = 20 oz of rice

If you are taking the rice from a 80-ounce bag, you will subtract the 20 oz away:

(80 oz) - (2 oz) * (10) = 80 oz - 20 oz = 60 ounces left.

The key idea is "how much is left", which points to subtraction. The bag is the source of the rice and the servings are being taken away. The remainder is left in the bag.