Question

If a sweet potato recipe calls for 3 cups of cooked mashed sweet potatoes to serve 8 people, how much would be needed to serve 4 people?

Answer 1

There will need to be 1.5 cups for 4 people.

Answer 2

To solve for this, we need to get proportions made by fractions.
Currently, we have 3 cups for 8 people, and x cups for 4 people. So our numerators (top number/variable of a fraction) are 3 and 8. Our denominators (bottom number/variable of a fraction) are x and 4.
Let's set these up as a proportion.
3/x = 8/4
To solve for x, we need to cross multiply the denominator of 3/x by the numerator of 8/4. This gives us 8x.
Now, cross multiply the numerator of 3/x and the denominator of 8/4. This gives us 12.
Our new equation is 8x = 12.
Divide both sides by 8 to get x.
8x / 8 = x.
12 / 8 = 1.5
x = 1.5
There will need to be 1.5 cups for 4 people.
I hope this helps!