Subtraction Review and Challenge

🎯 What You'll Learn

You will review all your subtraction skills and challenge yourself with harder problems.

🏪 Market Story

It's test day! Mrs. Okafor says, "Let's see if you can handle any subtraction problem I throw at you." Chidi, Amina, Bola, and the whole class are ready. Are you?

📝 Let's Learn

Review of subtraction strategies:

• Counting back: Great for subtracting small numbers.
• Counting up: Great for making change (start at the price, count up to what you paid).
• Borrowing: When the top digit is smaller than the bottom digit.
• Using doubles: If the number is a double, halving is easy.
• Subtracting from 100/1000: Ones from 10, tens from 9.

Challenge 1: ₦503 − ₦278. Ones: 3 − 8, borrow! 13 − 8 = 5. Tens: 9 − 7 = 2 (we had 10, borrowed 1, left 9... wait, 0 − 7, borrow from hundreds! 10 − 7 − 1 = 2). Hundreds: 4 − 2 = 2. Answer: ₦225.

Challenge 2: ₦1,000 − ₦463. Ones: 10 − 3 = 7. Tens: 9 − 6 = 3. Hundreds: 9 − 4 = 5. Answer: ₦537.

Challenge 3: Tunde has ₦750. He buys food for ₦285 and transport for ₦165. How much is left? Total spent: ₦285 + ₦165 = ₦450. Left: ₦750 − ₦450 = ₦300.

✏️ Practice Questions

1. ₦92 − ₦48 = ?
2. ₦500 − ₦237 = ?
3. Amina has ₦1,000. She buys a dress for ₦350 and shoes for ₦275. How much is left?

Click to see answers

1. ₦92 − ₦48 = ₦44. Ones: 2 − 8, borrow! 12 − 8 = 4. Tens: 8 − 4 = 4.
2. ₦500 − ₦237 = ₦263. Ones: 10 − 7 = 3. Tens: 9 − 3 = 6. Hundreds: 4 − 2 = 2.
3. Total: ₦350 + ₦275 = ₦625. Left: ₦1,000 − ₦625 = ₦375.

💡 Remember

You now have many subtraction strategies. Choose the best one for each problem. Always check your answer using addition — if the answer + what you subtracted = the original number, you got it right!