Answer: Choice A) 2/3 of a pound
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Here's one way to think of it
Imagine you had a cake that is cut into thirds (see figure 1 below). One full cake has 3 pieces. So three full cakes have 3*3 = 9 slices all together.
This means 3 = 9/3
Add on an extra slice (an extra one-third) and we get 9/3+1/3 = 10/3
So the mixed number 3 & 1/3 is the same as the improper fraction 10/3
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Now refer to figure 2. This is where we group up the ten slices into five groups. So there are 10/5 = 2 slices per container. Each slice is a third, so each container gets 2/3 a pound.