215 Addition Strategies

A

100

2. 212 + 487 = _______

699

200

4. 419 + 532 = ______

951

300

6. Lee School needs 407 folders for its students. Jefferson School needs 321 folders for its students. How many folders do both schools need?

728 folders

400

8. Tommy found 125 + 598. Since 598 is close to 600, he added 125 + 600 = 725. Then he subtracted 2 to get 723. Why did Tommy subtract 2? Explain.

Ex. Tommy subtracted 2 because he added 2 in the beginning. 598 + 2 = 600.

B

100

3. 874 + 109 = ______ 

983

200

5. 650 + 270 = _____

920

300

7. There are 229 people at the football game. 108 more people arrive at the game. How many people are at the football game now?

337 people

400

9. There are 192 ants on an ant farm. 397 more ants join the ant farm. How many ants are on the ant farm now? Use the number line to solve. Explain.

Ex. I started at 192 and added 300, then 90, and then 7. I landed on 589 so 192 + 397 = 589.