Billy, this is the solution to the exercise:
For answering it, we will use the Direct Rule of Three, this way:
Sugar (cups) Flour (cups)
2/3 2
x 5
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x * 2 = 5 * 2/3
2x = 10/3
Dividing by 2 at both sides:
2x/2 = 10/3 / 2
x = 10/3 * 1/2
x = 10/6
x = 1 2/3 (simplifying)
We will need 1 2/3 cups of sugar for 5 cups of flour
