Question

Tính bằng cách hợp lí nhất:

a) 17/25 x 13/19 + 17/25 x 6/19                            b) 47/19 : 15/32 - 47/19 : 15/17

cố giúp mình nha

Answer 1

a: =17/25(13/19+6/19)=17/25

b: \(=\dfrac{47}{19}\cdot\dfrac{32}{15}-\dfrac{47}{19}\cdot\dfrac{17}{15}=\dfrac{47}{19}\)

Answer 2

`17/25xx(13/19+6/19)`

`17/25xx1`

`17/25`

Answer 3

`a)17/25xx13/19+17/25xx6/19`

`=17/25xx(13/19+6/19)`

`=17/25xx19/19=17/25`

`b)47/19:15/32-47/19:15/17`

`=47/19xx32/15-47/19xx17/15`

`=47/19xx(32/15-17/15)`

`=47/19xx15/15=47/19`