Question
Will tied some pens into 10 bundles of 3 pens each. After he bought another 20 pens, he decided to tie them into bundles of 10 instead. How many bundles did he have in the end?
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Will tied some pens into 10 bundles of 3 pens each. After he bought another 20 pens, he decided to tie them into bundles of 10 instead. How many bundles did he have in the end?