Question

A soup recipe uses 3 pounds of meat to make 20 servings. How much is meet needed to make 15 servings?

Answer 1

Use proportions to solve.
"3 pounds of meat to make 20 servings"
aka, 3 pounds of meat PER 20 servings
Per, in math language, means divide
\(\large\rightarrow\Large\frac{3}{20}\)
"How much is meet needed to make 15 servings?"
aka, how much meat PER 15 servings
\(\large\rightarrow\Large\frac{m}{15}\)
Now, the ratios have to be equal, so...
\(\large\rightarrow\Large\frac{3}{20}=\frac{m}{15}\)

Solve for m. Do you know how to cross-multiply?