Question

几道简算

333*666=
2005*20062006-2006*20052005=
(44332-443.32)/(88664-886.64)=
0.1+0.3+0.5+0.7+0.9+0.11+0.11+0.13+...+0.95-0.97+0.99=
100+99-98+97-96...+3-2+1=
1989*1999-1988*2000=
9999*2222+3333*3334=
10*10-9*9+8*8-7*7+...+2*2-1*1=
(1+1.2)+(2+1.2*2)+(3+1.2*3)+...+(99+1.2*99)+(100+1.2*100)=

Answer 1

333*666
=(3*6)*(111*111)
=18*12321=221778
2005*20062006-2006*20052005
=2005*2006*10001-2006*2005*10001
=0
(44332-443.32)/(88664-886.64)
=(44332-443.32)/88664-(44332-443.32)/886.64
=44332/88664-443.32/88664-
44332/886.64+443.32/886.64
=0.5-0.005-50+0.5
=50.995
0.1+0.3+0.5+0.7+0.9+0.11+0.11+0.13+...+0.95-
0.97+0.99
=(0.1+0.9)*5/2+(0.11+0.99)*[(100-10)/2]/2
=1*5/2+1.1*[90/2]/2
=2.5+1.1*45/2
=2.5+24.75
=27.25
100+99-98+97-96...+3-2+1
＝（100+1）+(99-98)+(97-96)+…+（3-2）
＝101+1*49
＝150
1989*1999-1988*2000
＝(1988*1999+1999)-(1988*1999-1988)
＝（1988*1999-1988*1999）+（1999-1988）
＝11
9999*2222+3333*3334
=3333*(3*2222)+3333*3334
=3333*6666+3333*3334
=3333*(6666+3334)
=3333*10000
=33330000
10*10-9*9+8*8-7*7+...+2*2-1*1
=(9*10+9+1-9*9)+(8*7+7+1-7*7)+…+(2*1+1+1-1*1)
=(9*2+1)+(8*2+1)+…+(1*2+1)
=(1+2+…+10)*2+1*10
=[(1+10)*10/2]*2+10
=(1+10)*10+10
=(1+10+1)*10
=12*10
=120
(1+1.2)+(2+1.2*2)+(3+1.2*3)+...+(99+1.2*99)+
(100+1.2*100)
=(1+1.2)*(1+2+…+100)
=2.2*[(1+100)*100/2]
=2.2*[101*100/2]
=2.2*5050
=11110

Answer 2

333*666= 221778
2005*20062006-2006*20052005= 0
(44332-443.32)/(88664-886.64)= 0.5
1989*1999-1988*2000= 11
9999*2222+3333*3334= 33330000

Answer 3

333乘666= 221778
2005乘20062006-2006乘20052005=0
(44332减443.32)除(88664减886.64)=0.5
1989乘1999-1988乘2000=11
9999乘2222+3333乘3334=33330000

Answer 4

333*666= 221778;
2005*20062006-2006*20052005= 0 ;
(44332-443.32)/(88664-886.64)= 0.5 ;
100+99-98+97-96...+3-2+1=100+(99-98)+(97-96)+...+(3-2)+1=100+98/2+1=150;
0.1+0.3+0.5+0.7+0.9+0.11+0.11+0.13+...+0.95-0.97+0.99=(1+3+5+..+9)/10+(11+13+15+..+99)/100=(1+9)*5/2/10+(11+99)*89/2/100=2.5+48.95=51.45;
1989*1999-1988*2000= 11 ;
9999*2222+3333*3334= 33330000;
10*10-9*9+8*8-7*7+...+2*2-1*1=(10+9)*(10-9)+(8+7)*(8-7)+...(2+1)*(2-1)=10+9+8+7+...+2+1=(10+1)*10/2=55;
(1+1.2)+(2+1.2*2)+(3+1.2*3)+...+(99+1.2*99)+(100+1.2*100)=(1+2+3+..+100)+1.2*(1+2+3+..+100)=2.2*(1+2+3+..+100)=2.2*(1+100)*100/2=11110;