125X32、32X99、48X101、8.8除0.25、2100-998 这几道题怎么简便运算啊！

Question

要过程啊！

Answer 1

125×32
=125×8×4
=1000×4
=4000
32×99
=32×(100-1)
=32×100-32
=3200-32
=3168
48×101
=48×(100+1)
=48×100+48
=4800+48
=4848
8.8÷0.25
=8.8×(1÷0.25)
=8.8×4
=35.2
2100-998
=1100+1000-998
=1100+2
=1102

Answer 2

1. 125*32=125*(8*4)=125*8*4=1000*4=4000
2.32*(100-1)
3.48*(100+1)
4.(8+0.8)*0.25
5.2100-(100-2)