请看下面的解答: 25 × (4 × 12)×7= 25 × 4 × 12 × 7= 100 × 84= 8400
(25*4)*(12*7)=100*84=8400
25*4*(12*7)=100*84=8400
25X(4x12)X7=25x4x12x7=100x84=8400