Start this simply by looking for the specific value we're after: a fraction in teaspoons/cup.
That means the total number of teaspoons divided by the total number of cups. Remember that the figures we are given are in teaspoons PER CUP so we need to calculate the total number of teaspoons individually for each number of cups that we have:
2 teaspoons/cup * 3 cups = 6 teaspoons total
1 teaspoons/cup * 2.5 cups = 2.5 teaspoons total
3 teaspoons/cup * 4.5 cups = 13.5 teaspoons total
=22 teaspoons total
We now divide this by the total number of cups, which is simple: (3 + 2.5 + 4.5) cups = 10 cups
This means 22 teaspoons / 10 cups for 2.2 or
2 and 1/5 teaspoons per cup. Answer choice B.
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