1300÷25÷4, =1300÷(25×4), =1300÷100, =13; (262-26×7)÷40, =(262-182)÷40, =80÷40, =2; 192-(92-38), =192-92+38, =100+38, =138; 99×13+13, =(99+1)×13, =100×13, =1300; 32×25×125, =4×8×25×125, =(4×25)×(8×125), =100×1000, =100000; 104×28, =(100+4)×28, =100×28+4×28, =2800+112, =2912. |