A recipe for pizza crust call for 3 cups of flour for every 1 cup of water. How many cups of water are needed for 21 cups of flour I need help

The answer is 7 cups of water are needed for 21 cups of flour.

Shown work:
1 cup of water=3 cups of flours
? Cup of water=21 cups of flours

21 divided 3=7
1 multiply by 7= 7 cups of water needed

When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates. if you have a multiple-unit rate such as 120 students for every 3 buses, and want to find the single-unit rate, write a ratio equal to the multiple-unit rate with 1 as the second term.

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