Question

Tính hợp lí:

a) 29/9 - 3/8 - 11/9

b) 22/5 - 10/7 - 11/7

Answer 1

`a) 29/9 -3/8 -11/9`

`= (29/9-11/9) -3/8`

`= 18/9 -3/8=2-3/8`

`= 16/8 -3/8 =13/8`

`b) 22/5 - 10/7 - 11/7`

`=22/5 - (10/7 +11/7)`

`= 22/5 -21/7`

`= 22/5 - 3 = 22/5 - 15/5`

`= 7/5`

 

 

Answer 2

`29/9 - 3/8 - 11/9`

`=(29/9-11/9)-3/8`

`=2-3/8`

`=16/8-3/8`

`=13/8`

`22/5 - 10/7 -11/7`

`=22/5 - (10/7 +11/7)`

`=22/5 - 3`

`=22/5 - 15/5`

`=7/5`

Answer 3

`a) 29/9 - 3/8 - 11/9 = 29/9 - 11/9 = 18/9 - 3/8 = 2 - 3/8 = 16/8 - 3/8 = 13/8`

`b) 22/5 - 10/7 - 11/7 = 10/7 + 11/7 = 22/5 - 21/7 = 22/5 - 3 = 22/5 - 15/5 = 7/5`

Answer 4

`29/9 - 3/8 - 11/9`

`=(29/9 - 11/9)-3/8`

`=18/9 - 3/8`

`=2-3/8`

`=16/8-3/8`

`=13/8`

________________

`22/5 - 10/7 - 11/7`

`=22/5 -3`

`=22/5 - 15/5`

`=7/5`

 

Answer 5

a) \(\dfrac{29}{9}\) - \(\dfrac{3}{8}\) - \(\dfrac{11}{9}\)

= ( \(\dfrac{29}{9}\) - \(\dfrac{11}{9}\) ) - \(\dfrac{3}{8}\)

=          2       - \(\dfrac{3}{8}\)    

=                 \(\dfrac{13}{8}\)   

 

b) \(\dfrac{22}{5}\) - \(\dfrac{10}{7}\) - \(\dfrac{11}{7}\)

= \(\dfrac{22}{5}\) - ( \(\dfrac{10}{7}\) + \(\dfrac{11}{7}\) )

= \(\dfrac{22}{5}\) -          3

=            \(\dfrac{7}{5}\)