Hello Year 4! Today, we are going to learn how to multiply a three-digit number by a one-digit number. This is an important skill that will help you with many different math problems.

Understanding the Concept

When we multiply, we are adding a number to itself a certain number of times. For example, if we say 3 times 4, it means we are adding 3 four times:

$$3 + 3 + 3 + 3 = 12$$

Now, when we multiply a three-digit number by a one-digit number, we will use a method called “column multiplication.”

Step-by-Step Process

  1. Write the Numbers Down: Write the three-digit number on top and the one-digit number below it. Make sure to line up the numbers to the right.For example, let’s multiply 245 by 6: 245 x 6
  2. Multiply Each Digit: Start with the digit in the ones place of the three-digit number (the last digit). Multiply this digit by the one-digit number.For 245:
    • Multiply 5 (the last digit) by 6:
    $$5 \times 6 = 30$$Write down 0 and carry over 3.
  3. Continue with the Next Digit: Move to the next digit to the left. Remember to add any carry-over from the previous step.
    • Now multiply 4 by 6, and add the carry-over (3):
    $$4 \times 6 + 3 = 24 + 3 = 27$$Write down 7 and carry over 2.
  4. Finish with the Last Digit: Now do the same for the hundreds place:
    • Multiply 2 by 6 and add the carry-over (2):
    $$2 \times 6 + 2 = 12 + 2 = 14$$Write down 14.
  5. Combine the Results: Now read the final answer from top to bottom.

So, the final answer for 245 multiplied by 6 is 1470.

Key Rules

  • Always start multiplying from the rightmost digit.
  • Don’t forget to carry over when you get a number larger than 9.
  • Line up the numbers correctly when writing them down.

Tips and Tricks

  • Practice with smaller numbers first to build your confidence.
  • Use graph paper to help keep your columns straight.
  • Double-check your work by adding the groups together to see if you get the same answer.

Practice Questions

Easy Level Questions

  1. 123 x 2 = ?
  2. 150 x 3 = ?
  3. 200 x 4 = ?
  4. 310 x 5 = ?
  5. 450 x 1 = ?
  6. 321 x 2 = ?
  7. 234 x 3 = ?
  8. 410 x 2 = ?
  9. 560 x 1 = ?
  10. 120 x 4 = ?
  11. 250 x 2 = ?
  12. 300 x 3 = ?
  13. 140 x 1 = ?
  14. 220 x 4 = ?
  15. 330 x 2 = ?
  16. 400 x 5 = ?
  17. 150 x 1 = ?
  18. 240 x 3 = ?
  19. 180 x 2 = ?
  20. 260 x 5 = ?

Medium Level Questions

  1. 375 x 4 = ?
  2. 482 x 3 = ?
  3. 249 x 5 = ?
  4. 563 x 2 = ?
  5. 678 x 6 = ?
  6. 810 x 7 = ?
  7. 410 x 8 = ?
  8. 532 x 4 = ?
  9. 294 x 3 = ?
  10. 725 x 2 = ?
  11. 150 x 6 = ?
  12. 670 x 5 = ?
  13. 450 x 3 = ?
  14. 385 x 7 = ?
  15. 246 x 2 = ?
  16. 870 x 1 = ?
  17. 460 x 4 = ?
  18. 590 x 3 = ?
  19. 342 x 5 = ?
  20. 215 x 6 = ?

Hard Level Questions

  1. 729 x 8 = ?
  2. 847 x 9 = ?
  3. 962 x 7 = ?
  4. 483 x 6 = ?
  5. 237 x 5 = ?
  6. 654 x 4 = ?
  7. 891 x 3 = ?
  8. 705 x 6 = ?
  9. 829 x 9 = ?
  10. 456 x 8 = ?
  11. 312 x 7 = ?
  12. 234 x 6 = ?
  13. 378 x 5 = ?
  14. 814 x 3 = ?
  15. 519 x 4 = ?
  16. 645 x 2 = ?
  17. 473 x 8 = ?
  18. 786 x 5 = ?
  19. 123 x 9 = ?
  20. 905 x 7 = ?

Answers with Explanations

Easy Level Answers

  1. 246
  2. 450
  3. 800
  4. 1550
  5. 450
  6. 642
  7. 702
  8. 820
  9. 560
  10. 480
  11. 500
  12. 900
  13. 140
  14. 880
  15. 660
  16. 2000
  17. 150
  18. 720
  19. 360
  20. 1300

Medium Level Answers

  1. 1500
  2. 1446
  3. 1245
  4. 1126
  5. 4068
  6. 5670
  7. 3280
  8. 2128
  9. 882
  10. 1450
  11. 900
  12. 3350
  13. 1350
  14. 2695
  15. 492
  16. 870
  17. 1840
  18. 1770
  19. 1710
  20. 1290

Hard Level Answers

  1. 5832
  2. 7623
  3. 6734
  4. 2898
  5. 1185
  6. 2616
  7. 2673
  8. 4230
  9. 7461
  10. 3648
  11. 2184
  12. 1404
  13. 1890
  14. 2442
  15. 2076
  16. 1290
  17. 3784
  18. 3930
  19. 1107
  20. 6335

Happy multiplying, Year 4! Remember, practice makes perfect!