Answers

2015-09-14T15:21:53+08:00
90 / 10 = 9
1. 9, Lorena should buy 9 packs of biscuits to get 90 pieces of it.

90 / 15 = 6
2. 6, Lorena should buy 6 packs of biscuits to get 90 pieces of it.

90 / 20 = 4 and 1/2
3. 4.5 or 4 and 1/2, Lorena should but 4 and half of a pack biscuits to get 90 pieces of it. 
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