Subtract 2-Digit Numbers Vertically
š„ Stack Em High! The problems are back... but what if there is no Tens number on the bottom?
Concept
Most vertical subtraction is easy. But there is one specific type of problem that tricks everyone! šÆ **The "Empty Spot" Trick:** **Problem: 64 - 8 = ?** Look at how they stacked it! 6 4 - 8 -------- 1. **Floor Check:** 8 is bigger than 4. Go next door to the 6. Make it a 5. Make the 4 a 14. 2. **Ones:** 14 - 8 = 6. 3. **Tens:** The top number is now a 5. But what is under it? NOTHING! 4. **Bring it down!** An empty space is just an invisible zero! (5 - 0 = 5). Just drop the 5 down. 5. **Answer:** 56.
Try it
Drop the invisible zero! **Instructions:** Borrow if you need to, then drop the top Tens number straight down. **Problem 1:** 4 1 - 5 -------- * Floor check! Borrow from 4. * Ones: 11 - 5 = ___ * Tens: 3 - 0 = ___ * Answer: ___ **Problem 2:** 8 5 - 9 -------- * Answer: ___ **Problem 3:** 2 2 - 7 -------- * Answer: ___ **Problem 4:** 5 8 - 3 -------- * (Hint: Trick problem! Don't borrow! Just drop the 5!) * Answer: ___