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2025 Math Kangaroo

Problem 5

Problem 5 · 2025 Math Kangaroo Easy
Fractions, Decimals & Percents proportion

In a recipe, Ruben needs 1½ cups of water for 1 cup of rice. Ruben wants to use 1½ cups of rice. How many cups of water does he need?

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Answer: D — 2¼
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Hint 1 of 2
The water needed is proportional to the rice used.
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Hint 2 of 2
Multiply 1½ cups of water by 1½ cups of rice.
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Approach: scale the ratio
  1. Water = 1.5 cups per cup of rice.
  2. For 1.5 cups of rice: 1.5 × 1.5 = 2.25 cups.
  3. That is cups.
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