Answer: Choice B
The bread recipe calls for 2 more cups of flour per cup of sugar than the cookie recipe.
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Step-by-step explanation:
I'll use this shorthand
Something like "2 cups of sugar" will shorten to "2s".
The cookies need 3s for every 6f.
Therefore we get this ratio
3s : 6f
And we can divide both sides by 3 to end up with
s : 2f
Meaning "each cup of sugar needs 2 cups of flour".
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Meanwhile, the bread recipe calls for 2s for every 8f.
2s : 8f
2s/2 : 8f/2 .... divide both sides by 2
s : 4f
When making bread, each cup of sugar needs 4 cups of flour. In other words, the amount of flour is quadruple that of the sugar.
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Recap
- Cookies have the ratio of s : 2f
- Bread has the ratio of s : 4f
These ratios are reduced so that we have "s" on the left side without any numbers attached to it. In other words, we have 1s.
We can see that the bread needs 2 more cups of flour compared to the cookies (since 4f - 2f = 2f). It's important that we reduce those ratios so that we're talking about the same amount of sugar for each food item.
This is why choice B is the final answer.
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An example:
Each food item will use 1 cup of sugar.
The cookies need twice the amount of flour, so the cookies require 2 cups of flour (because of the ratio s:2f mentioned earlier).
The bread needs quadruple the amount of flour compared to sugar. Meaning the bread needs 4 cups of flour (because of the ratio s:4f).
Then subtract to get
(4 cups flour for bread) - (2 cups flour for cookies) = 2 cups flour