(1)240÷15÷4, =240÷(15×4), =240÷60, =4; (2)129+318+71, =(129+71)+318, =200+318, =518; (3)304+278, =(300+4)+(300-22), =300+300-(22-4), =600-18, =582; (4)25×(17×8), =25×8×17, =(25×4)×(2×17), =100×34, =3400; (5)(614+346)÷48, =960÷48, =20; (6)94×(205-188), =94×17, =1598; (7)25×32×125, =25×4×8×125, =(25×4)×(8×125), =100×1000, =100000; (8)420÷35, =420÷(7×5), =420÷7÷5, =60÷5, =12. |