一、小学1年级10道数学题~ 简便计算,有能力的来啊
1、52又11/25*79.45+159*47.56+79又11/20*52.44
=52.44*79.45+159*47.56+79.55*52.44
=52.44*(79.45+79.55)+159*47.56
=52.44*159+159*47.56
=159*(52.44+47.56)
=159*100
=15900
2、5/9*193+4/9*195
=5/9*(195-2)+4/9*195
=5/9*195-5/9*2+4/9*195
=195*(5/9+4/9)-5/9*2
=195-10/9
=193又8/9
3.2001*20022002-2002*20012001
=2002*20022002-2002*2001
=2002*(2002)-20022002
=2002*1
=2002*(10001-10001)
=0
4、1.9+19.9+199.9+1999.9+19999.9 =(2+20+200+2000+20000)-(0.1+0.1+0.1+0.1+0.1)=22221.5
5.3901*99/(3901*198)*1110
=(3901/3901)*(99/198)*1110
=1*(1/2)*1110
=555
6.10又3/8*18.88+18.88*0.625-188.8*1/10
=10.375*18.88+18.88*0.625-18.88
=18.88*(10.375+0.625-1)
=188.8
7.2002++1998++……+2+1
=(2002+)+(1998+)+……+2+1
=4+4+4+……+2+1
=4*500+2+1
=2003
8.1/1*2+1/2*3+1/3*4+……+1/10*11
=(1-1/2)+(1/2-1/3)+(1/3-1/4)+(1/4-1/5)+(1/5-1/6)+(1/6-1/7)+(1/7-1/8)+(1/8-1/9)+(1/9-1/10)+(1/10-1/11)
=1-1/11
=10/11
9.1/3+1/15+1/35+1/63+1/99
=1/2*(1-1/3)+1/2*(1/3-1/5)+1/2*(1/5-1/7)+1/2*(1/7-1/9)+
1/2*(1/9-1/11)
=1/2*(1-1/3+1/3-1/5+1/5-1/7+1/7-1/9+1/9-1/11)
=1/2*10/11
=5/11
10、1又1/2-5/6+7/12+9/20+11/30-13/42+15/56
=(1+1/2)-(1/2+1/3)+(1/3+1/4)-(1/4+1/5)+(1/5+1/6)-(1/6+1/7)+(1/7+1/8)
=1+1/2-1/2-1/3+1/3+1/4+1/4+1/5+1/5+1/6-1/6-1/7+1/7+1/8
=1+1/4+1/4+1/5+1/5+1/8
=2.025
二、小学数学一年级口算题
3+2.5+7
三、小学数学速算 题目
1.1+2+2+……+18=(1+18)*18/2=
2.1+4+7+10+13+16+19=(1+19)*7/2=
3.2+9+16+23+30+37+44=(2+44)*7/2=
4.2+4+6+8+……+28=(2+28)*14/2=