The ageold question about when a student will use a concept from math class comes full circle when you steam rice. Calculating how much rice and water to use triggers what you learned about ratios and proportions in those longforgotten lessons. Many cookbooks recommend 1 1/2 cups of water to 1 cup of uncooked rice to make four 1/2cup servings, which gives you the starting points for the two different ratios you’ll need.
Things You'll Need
 Paper
 Pencil
How Much Rice for Your Guest List

Write down the ratio of rice to servings you already know, which is 1:4. Rewrite the ratio as the fraction 1/4.

Write another fraction next to the first, with the number of servings you need on the bottom. For example, for eight people, write 1/4 = R/8, with the “R” standing for the rice amount. For two people, the equation would be 1/4 = R/2.

Crossmultiply so that you have 1 x number of people = 4 x R. For the first example, this means 8 = 4R. For the second example, it would be 2 = 4R.

Divide everything by four to get the cups of rice needed. For eight people, use 2 cups of uncooked white rice; for two people, use 1/2 cup.
How Much Water for the Rice

Write the known ratio: 1.5:1 (1 1/2 cup of water to 1 cup of rice). Write it as a fraction: 1.5/1.

Write the new ratio as “W” (for water) over rice. For 2 cups of uncooked rice, that means 1.5/1 = W/2.

Crossmultiply for the equation. The example gives you 1.5 x 2 = 1 x W.

Multiply the ratio. In the example, you would find 3 = W. Use 3 cups of water for 2 cups of uncooked white rice.
References
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