Question

1, Tính hợp lý:
a, 768 + 759 - (468 + 559)               b, 720 : 6 - 360 : 3 + 291
c, 529 x 371 - 371 x 329                  d, 1024 : 16 - 312 : 8

Answer 1

a. 768 + 759 - (468 + 559) = 768 + 759 - 468 - 559 = (768-468)+(759-559)=300+200=500

b. (120 - 120) + 291 = 291

c. 371(529-329)=371*200=74200

d. 64-39=25

Answer 2

`768 + 759 - (468 + 559)`

`= 768 + 759 - 468 - 559`

`= (768-468) + (759-559)`

`=300+200=500`

______________________________________

`720 : 6 - 360 : 3 + 291`

`=120 - 120+291`

`=(120 - 120) + 291`

`= 0+219`

`=219`

_____________________________________

`529 xx 371 - 371 xx329 `

`=371xx(529-329)`

`=371xx200`

`=74200`

______________________________________

`1024 : 16 - 312 : 8`

`=64-39`

`=25`