a) 3000 + 5000 = 8000

      5000 + 5000 = 10 000

      4000 + 4000 = 8000

      7000 + 2000 = 9000

      6000 + 1000 = 7000

      2000 + 8000 = 10 000

b) 2000 + 700 = 2700

      100 + 1000 = 1100

      6000 + 600 = 6600

      8000 + 500 = 8500

      5000 + 300 = 5300

      400 + 6000 = 6400

a) 3000+5000=8000

5000+5000=10000

4000+4000=8000

7000+2000=9000

6000+1000=7000

2000+8000=10000

b) 2000+700=2700

100+1000=1100

6000+600=6600

8000+500=8500

5000+300=5300

400+6000=6400

Theo quy tắc của dấu ngoặc,ta có:

516+320+357+5000+612-(516+320)-(5000+357+612)+(-420)+(-580)

= 516+320+357+5000+612-516-320-5000-357-612+(-420)+(-580)

= (516-516)+(320-320)+(357-357)+(5000-5000)+(612-612)+(-420)+(-580)

= 0 + 0 + 0 + 0 + 0 + (-420)+(-580)

= 0 + 0 + 0 + 0 + (-420)+(-580)

= 0 + 0 + 0 + (-420)+(-580)

= 0 + 0 + (-420)+(-580)

= 0 + ((-420)+(-580))

= 0 + -1000

= -1000

= 10000

10000

5000 + 5000 + 10000

= 5000 x 2 + 10000

= 10000 + 10000

= 10000 x 2

= 20000

5000+5000+10000

=10000+10000

=20000

ai k mình mình k lại

200000

5000+5000+10000

=10000+10000

=20000

tk nhé

\(5000+5000+10000=20000\)

chuc bn hoc gioi!

~~~~~~~~~~~~~~~~

nhae@ ^_^

5000+5000+10000

=10000+10000

=20000

ai k mình mình k lại

=1000 nha bạn

5000+5000-9000=1000

20000

5000+5000+10000=20000