5000 + 100 = 5100

7400 - 400 = 7000

2000 3 + 600 = 6600

8000 : 2 + 2000 = 6000

6000 - (5000 - 1000) = 2000

6000 - 5000 + 1000 = 2000

7000 - 3000 x 2 = 1000

(7000 - 3000) x 2 = 8000

a) 9000 - 7000 = 2000

     3000 - 2000 = 1000

     8000 -8000 = 0

     5000 - 1000 = 4000

     6000 - 5000 = 1000

     10000 - 2000 = 8000

b) 4600 - 400 = 4200

     8500 - 500 = 8000

     9900 - 300 = 9600

     6800 - 700 = 6100

     7200 - 3000 = 4200

     5600 - 2000 = 3600

     3800 - 3000 = 800

     7400 - 400 = 7000

2000 + 400 = 2400

9000 + 900 = 9900

300 + 4000 = 4300

600 + 5000 = 5600

7000 + 800 = 7800

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) Mẫu: 5000 + 200 + 70 + 8 = 5278

7000 + 600 + 50 + 4 = 7654

2000 + 800 + 90 + 6 = 2896

8000 + 400 + 20 + 7 = 8427

9000 + 900 + 90 + 9 = 9999

b) Mẫu: 4000 + 20 + 1 = 4021

3000 + 60 + 8 = 3068

7000 + 200 + 5 = 7205

9000 + 50 + 6 = 9056

2000 + 100 + 3 = 2103

5000 + 7 = 5007

9000 + 9 = 9009

3000 + 300 + 3 = 3303

8000 + 700 + 5 = 8705

 7618 = 7000 + 600 + 10 + 8

9274 = 9000 + 200 + 70 + 4

4404 = 4000 + 400 + 4

1942 = 1000 + 900 + 40 + 2

5076 = 5000 + 70 + 6

2005 = 2000 + 5

b) 5000 + 700 + 20 + 4 = 5724

6000 + 800 + 90 + 5 = 6895

5000 + 500 + 50 + 5 = 5555

2000 + 400 = 2400

2000 + 20 = 2020

2000 + 7 = 2007