Use Compensation to Subtract up to 3 Digits
π¦ The Bandit strikes again! A terrible number like 199 is trying to ruin your day. Steal exactly 200, and give 1 back!
Do this: Read the concept below, then try the quiz or activity.
Concept
When you see numbers ending in 98 or 99, never stack them and try to borrow. It takes forever.
π― The "Steal and Return" Strategy: Example: 546 - 299 = ? Subtracting 299 requires double borrowing. It is a nightmare.
1. The Trick: 299 is practically 300. Just steal 300! 2. The Math: 546 - 300 = 246. (Super easy, just spinning the hundreds dial!). 3. Wait! I stole TOO MUCH. I was only supposed to take 299 things. I accidentally took 1 extra thing. 4. The Fix: I must GIVE ONE BACK. (ADD 1!). 246 + 1 = 247! 5. Answer: 247.
You successfully subtracted an insane number entirely inside your head.
Try it
Steal too much, pay it back!
Instructions: Subtract a perfect hundred, then ADD exactly 1 or 2 back onto your answer to fix the theft!
Problem 1: 832 - 199 = ? * Steal 200! (832 - 200 = _____ ). * Give 1 back! (Add +1). * Answer: ___
Problem 2: 651 - 398 = ? * Steal 400! (651 - 400 = _____ ). * Give 2 back! (Add +2, because 398 is 2 away from 400!). * Answer: ___
Problem 3: 477 - 99 = ? * Answer: ___
Problem 4: 914 - 498 = ? * Answer: ___