There are eight boxes, and the toffees in each box are 9, 17, 24, 28, 30, 31, 33, and 44 pieces. A takes away one box first, and the other boxes are taken away by B, C, and D respectively. It is known that the number of pieces of sugar obtained by B and C is the same, and both are twice that of D. Ask how many pieces of toffee are in the box that A takes away? (briefly explain why)
有八个盒子，各盒内装的奶糖分别为9、17、24、28、30、31、33和44块．甲先取走了一盒，其余各盒被乙、丙、丁分别取走．已知乙、丙取到的糖的块数相同，且都为丁的2倍．问甲取走的盒中有多少块奶糖？(简要说明理由)
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