Add Two-Digit Numbers Vertically (Sums to 200)
š Breaking the 100 barrier! What happens when the Tens column adds up to more than 10? You just carry it to the Hundreds column!
Concept
We already learned how to "Carry the 1" from the Ones column. But what if the Tens column is huge? šÆ **The Double-Carry Trick:** **Example: 85 + 67 = ?** 1. **Ones Column:** 5 + 7 = 12. Write the 2, carry the +1 to the Tens. 2. **Tens Column:** 1 + 8 + 6. * 1+8=9. 9+6=15! * Uh oh. You can't fit 15 in the Tens column. 3. **Bring in the Hundreds:** * Write the **5** in the Tens column. * Write the **1** directly into the Hundreds column on the left! 4. **Answer:** **152**. It's just carrying, doing it twice in a row instead of once!
Try it
Break the 100 barrier! **Instructions:** Add down the Ones column (carry if you need to). Add down the Tens column (carry to the Hundreds if you need to!). **Problem 1:** 6 4 + 8 2 --------- * Ones: 4 + 2 = ___ * Tens: 6 + 8 = 14. Write the 4, put the 1 in the hundreds! * Total Answer: 14___ **Problem 2:** 7 8 + 4 5 --------- * Answer: ___ **Problem 3:** 9 3 + 9 3 --------- * Answer: ___ **Problem 4:** 8 8 + 5 5 --------- * Answer: ___