Question

数学巧算四道题，求帮解：

1.125x88+404x25=?
2.320x44+68x440=?
3.79x79-79+22x79=?
4.25x57+25x42+25=?

Answer 1

1. 125x88+404x25
=125x8x11+101x4x25
=11000+10100
=21100
2. 320x44+68x440
=44x(320+680)
=44x1000
=44000
3.79x79-79+22x79
=79x(79-1＋22）
=79x100=7900
4.25x57+25x42+25
=25x（57＋42＋1)
=25x100=2500

Answer 2

34+34x99=34x1+34x99=34x（1+99）=34x100=3400
35x35+35x64+35=35x35+35x36+35x1=35x（36+35+1）=35x72=2520
173x73-73x73=73x（173-73）=73x100=7300
98x37=37x（100-2）=3700-74=3626
99x49+49=49x（99+1）=49x100=4900
125x9-125=125x（9-1）=125x8=1000

Answer 3

1. 125*8*11+25*4*101=1000*11+100*101=11000+10100=21100

2. 44*(320+680)=44*1000=44000

3. 79*(79-1+22)=79*100=7900

4. 25*(57+42+1)=25*100=2500

Answer 4

1.  125*8*11+（400+4）*25=11000+10000+100=21100

2. 32*440+68*440=（32+68）*440=44000

3. 79*（79-1+22）=79*100=7900

4. 25*（57+42+1）=25*100=2500
   

Answer 5

1，原式=125×8×11＋4×101×25＝1000×11＋100×101＝11000＋10100＝21100
2，原式＝32×440＋68×440＝（32＋68）×440＝44000
3，原式＝79×﹙79－1＋22﹚＝79×100＝7900
4，原式＝25×﹙57＋42＋1﹚＝25×100＝2500

Answer 6

1.125*80+125*8+400*25+4*25=21100
2.44*（320+68*10）=44000
3.79*（79-1+22）=7900
4.25*（57+42+1）=2500