Three-digit + and − worksheet

Part A: Working out and filling in

1. 1. 192 + 218 = 410

   192 + 218: left to right, add one place at a time: hundreds 192 + 200 = 392, tens 392 + 10 = 402, ones 402 + 8 = 410

2. 2. 879 − 385 = 494

   879 − 385: left to right, subtract one place at a time: hundreds 879 − 300 = 579, tens 579 − 80 = 499, ones 499 − 5 = 494

3. 3. 743 − 305 = 438

   743 − 305: left to right, subtract one place at a time: hundreds 743 − 300 = 443, ones 443 − 5 = 438

4. 4. 452 − 346 = 106

   452 − 346: left to right, subtract one place at a time: hundreds 452 − 300 = 152, tens 152 − 40 = 112, ones 112 − 6 = 106

5. 5. 651 + 163 = 814

   651 + 163: left to right, add one place at a time: hundreds 651 + 100 = 751, tens 751 + 60 = 811, ones 811 + 3 = 814

6. 6. 255 + 595 = 850

   255 + 595: left to right, add one place at a time: hundreds 255 + 500 = 755, tens 755 + 90 = 845, ones 845 + 5 = 850

7. 7. 498 − 179 = 319

   498 − 179: left to right, subtract one place at a time: hundreds 498 − 100 = 398, tens 398 − 70 = 328, ones 328 − 9 = 319

8. 8. 985 − 839 = 146

   985 − 839: left to right, subtract one place at a time: hundreds 985 − 800 = 185, tens 185 − 30 = 155, ones 155 − 9 = 146

9. 9. 759 − 201 = 558

   759 − 201: left to right, subtract one place at a time: hundreds 759 − 200 = 559, ones 559 − 1 = 558

10. 10. 616 − 309 = 307

    616 − 309: left to right, subtract one place at a time: hundreds 616 − 300 = 316, ones 316 − 9 = 307

11. 11. 703 − 214 = 489

    703 − 214: left to right, subtract one place at a time: hundreds 703 − 200 = 503, tens 503 − 10 = 493, ones 493 − 4 = 489

12. 12. 450 + 158 = 608

    450 + 158: left to right, add one place at a time: hundreds 450 + 100 = 550, tens 550 + 50 = 600, ones 600 + 8 = 608

Part B: Word problems

Marking: 2 for the working, 1 for the answer, 1 for the sentence.

1. 13. A photocopier printed 467 sheets in the morning and 254 more in the afternoon than in the morning. How many sheets did it print in the afternoon? (Answer: 721 sheets)

   467 + 254 = 721

2. 14. A cinema has 331 seats, and 236 tickets have been sold for tonight. How many seats are still not sold? (Answer: 95 seats)

   331 − 236 = 95

3. 15. A library had 332 books and bought 139 more this year. How many books does the library have now? (Answer: 471 books)

   332 + 139 = 471

4. 16. Chi-keung has saved $638 and buys a game console for $367. How many dollars does he have left? (Answer: 271 dollars)

   638 − 367 = 271

5. 17. A cinema has 806 seats, and 249 tickets have been sold for tonight. How many seats are still not sold? (Answer: 557 seats)

   806 − 249 = 557

6. 18. Ka-yan has saved $617 and buys a game console for $252. How many dollars does she have left? (Answer: 365 dollars)

   617 − 252 = 365