Answer: Each bag gets 1/5 of a pound
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Step-by-step explanation:
Let's say that we had 9 blocks that were each one-tenth of a pound.
This means we have 9*(1/10) = 9/10 of a pound total.
Take 1/3 of this to get (1/3)*9 = 9/3 = 3. So we take away 3 blocks to represent the amount of oranges she has eaten so far.
We're left with 9-3 = 6 blocks.
Divide these 6 blocks among 3 bags getting 6/3 = 2 blocks per bag.
Each block is 1/10 of a pound, so 2*(1/10) = 2/10 = 1/5 of a pound goes per bag.
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Another approach:
1/3 of 9/10 = (1/3)*(9/10) = 9/30 = 3/10
She has eaten 3/10 of a pound of oranges, leaving 9/10-3/10 = 6/10 = 3/5 of a pound left.
Dividing 3/5 over 3 leads to
(3/5) divided by (3/1) = (3/5)*(1/3) = 3/15 = 1/5