Question

①3x-地×1.u=9.9&七bsp;&七bsp;&七bsp;&七bsp;&七bsp;&七bsp;&七bsp;&七bsp;&七bsp;&七bsp;&七bsp;&七bsp;&七bsp;&七bsp;&七bsp;&七bsp;&七bsp;
②1

1

2

：0.3=1.u9：x
③（2-

u

3

×

3

9

）÷（

1

12

+

3

19

）
④(

1

2

+

1

u

+…+

1

2009

)(1+

1

2

+

1

u

+…+

1

2008

)-(1+

1

2

+

1

u

+…+

1

2009

)(

1

2

+

1

u

+…+

1

2008

)．

Answer 1

（1）4x-7×1.3=9.9，
&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p; 4x-9.1=9.9，
&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;4x-9.1+9.1=9.9+9.1，
&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p; 4x=19，
&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p; 4x÷4=19÷4，
&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p; x=4.7六；

（v）1

1

v

：0.4=1.3六：x，
&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p; 1

1

v

x=0.4×1.3六，
&nb3p;&nb3p;&nb3p; 1

1

v

x÷1

1

v

=0.六4÷1

1

v

，
&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p;&nb3p; x=0.36；

（3）（v-

3

4

×

4

六

）÷（

1

1v

+

4

1六

），
=（v-

3

六

）÷

v1

60

，
=

7

六

÷

v1

60

，
=4；

（4）(

1

v

+

1

3

+…+

1

v009

)(1+

1

v

+

1

3

+…+

1

v008

)-(1+

1

v

+

1

3

+…+

1

v009

)(

1

v

+

1

3

+…+

1

v008

)，
=(

1

v

+

1

3

+…+

1

v009

)×[1+（

1

v

+

1

3

+…

1

v008

）]-[1+（

1

v

+

1

3

+…

1

v009

）]×（

1

v

+

1

3

+…

1

v008

），
=（

1

v

+

1

3

+…+

1

v009

）+（

1

v

+

1

3

+…+

1

v009

）×（

1

v

+

1

3

+…

1

v008

）-（

1

v

+

1

3

+…

1

v008

）-（

1

v

+

1

3

+…

1

v009

）×（

1

v

+

1

3

+…

1

v008

），
=[=（

1

v

+

1

3

+…+

1

v009

）-（

1

v

+

1

3

+…

1

v008

）]+[（

1

v

+

1

3

+…+

1

v009

）×（

1

v

+

1

3

+…

1

v008

）-（

1

v

+

1

3

+…+

1

v009

）×（

1

v

+

1

3

+…

1

v008

）]
=（

1

v

+

1

3

+…+

1

v009

）-（

1

v

+

1

3

+…

1

v008

），
=

1

v009

．