25x(4x4)=400
25x16
=25x4x4
=100x4
=400
125×25x16
=125×25x8x2
=(125x8)x(25x2)
=1000x50
=50000
=25*4*16=100*16=1600
原式
=2.5x3x16.7+8.3x2.5+2.5x1.6
=2.5x50.1+8.3x2.5+2.5x1.6
=2.5x(50.1+8.3+1.6)
=2.5x(58.4+1.6)
=2.5x60
=2.5x4x15
=10x15
=150
25x16-16x15
=16x(25-15)
=160
25X5X16
=(25×4)×(5×4)
=100×20
=2000
25x4=100;
125x8=1000;
25x16
=25x4x4
=100x4
=400;
25x48
=25x4x12
=100x12
=1200.
供参考。
316x16-16x16
=(316-16)x16
=300x16
=4800
25×16
=25×(4×4)
=25×4×4
=100×4
=400