Doubles, Near Doubles, and Adding Three Numbers Using Doubles and Near Doubles

Doubles

100

2 + 2

4

200

3 +3

6

300

4+4

8

400

7+7

14

500

9+9

18

Near Doubles

100

2+3

5

200

4+5

9

300

6+7

13

400

8+9

17

500

9+10

19

Doubles Riddles

100

2+?=4

2

200

5+?=10

5

300

6+?=12

6

400

7+?=14

7

500

9+?=18

9

double the Middle

100

1+3=

4

200

3+5=

8

300

5+7=

12

400

8+6=

14

500

7+9=

16

Make 10

100

6+___=10

6+4=10

200

5+___=10

5+5=10

300

7+___=10

7+3=10

400

3+___=10

3+7=10

500

8+___=10

8+2=10