There are 50 - 5 = <<50-5=45>>45 chocolates in three boxes.
So, each box is filled with 45/3 = <<45/3=15>>15 chocolates.
5 + 25 = <<5+25=30>>30 chocolates are needed to be placed in boxes.
Hence, they needed 30/15 = <<30/15=2>>2 boxes for the 30 chocolates.
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