Answer :
How many ounces are in a pound? 16! SO 16 times 4 = 64. So Nancy needs 64 ounces in all. So 28 plus 10 = 38 that's still not enough, so lets add some more 38 plus 10 = 48 still not enough, add some more 48 plus 10 plus 10 = 68. So lets add up how many bags we need. So in all with her 28 that she already has, we need 4 bags.