add y2 add 2digit

What you'll learn

1. 1

   To add two 2-digit numbers, add the tens and the ones separately, then put them back together.

2. 2

   34 + 23. Tens: 30 + 20 = 50. Ones: 4 + 3 = 7. Together: 57.

3. 3

   What is 42 + 35?

4. 4

   Sometimes the ones make ten or more. Ten ones can be swapped for one ten — we call that exchanging.

5. 5

   28 + 15. Ones: 8 + 5 = 13. That is 1 ten and 3 ones. Tens: 20 + 10 + the new 10 = 40. Answer: 43.

6. 6

   What is 47 + 26?

7. 7

   Sam says 47 + 26 = 613. What did Sam do wrong?