A recipe for 1 batch of muffins included 2/3 cup of raisins. Ina made 2 1/2 batches of muffins. How many cups of raisins did she use?

you have to take 2/3 times 2 1/2 which will give you 5/3

1 batch of muffins = 2/3 of cup
2 1/2 = 5/2 batches of muffins

Total cups of raisins = 5/2 * 2/3
                                 = 5/3

Therefore, total number of cups of raisins used is 5/3 cups..