卖西瓜

+ 1 ) = 40(张) 10

2÷(1- 1 − 1 ) = 2÷ 1 = 8(个)

2 4 4

8÷(1- 1 − 1 ) = 8÷ 1 = 32(个)

2 4 4

32÷(1- 1 − 1 ) = 32÷ 1 = 128(个)

2 4 4

共有 128 个西瓜