Year 6 Maths: Multiplying Decimal by a Two Digit Number

Introduction

Hello, Year 6! Today, we are going to learn how to multiply a decimal number by a two-digit number. This is an important skill that you will use in many real-life situations, like shopping, cooking, or budgeting. Let’s break it down step-by-step!

Understanding Decimals

Decimals are numbers that have a point, like 0.5 or 2.75. The number before the decimal point is a whole number, and the numbers after the decimal point show parts of a whole.

Step-by-Step Guide to Multiplying Decimals

Step 1: Ignore the Decimal Point

First, for our calculation, we’ll pretend the decimal doesn’t exist. For example, if we have 2.5, we will think of it as 25.

Step 2: Multiply

Next, multiply the whole number (as if the decimal is not there) by the two-digit number.

Example:

If we want to find 2.5 × 12, we will first calculate:

Step 3: Place the Decimal

Now, we need to add the decimal back in. Count how many digits are after the decimal point in the original decimal number. In 2.5, there is 1 digit after the decimal point.

So, we place the decimal point in our answer (300) to make it 30.0.

Final Answer:

Key Rules

1. Ignore the decimal point when multiplying.
2. Multiply as if both numbers are whole.
3. Count the decimal places in the original decimal.
4. Place the decimal in the answer based on the count from step 3.

Tips and Tricks

• Practice with smaller numbers to gain confidence.
• Check your work: After you place the decimal, read your answer to make sure it makes sense.
• Use a calculator to check your answers if you’re unsure.

Questions

Now it’s time to practice what you’ve learned! Here are some questions for you to try.

Easy Level (Questions 1-20)

1. What is 0.5 × 11?
2. What is 1.2 × 10?
3. What is 3.4 × 12?
4. What is 0.8 × 25?
5. What is 2.1 × 20?
6. What is 4.5 × 13?
7. What is 0.6 × 14?
8. What is 1.5 × 15?
9. What is 2.0 × 16?
10. What is 0.9 × 18?
11. What is 3.3 × 11?
12. What is 1.8 × 10?
13. What is 2.2 × 12?
14. What is 0.7 × 20?
15. What is 4.0 × 14?
16. What is 0.4 × 25?
17. What is 1.1 × 19?
18. What is 2.5 × 10?
19. What is 3.0 × 13?
20. What is 0.3 × 30?

Medium Level (Questions 21-40)

21. What is 2.6 × 14?
22. What is 3.7 × 12?
23. What is 1.9 × 15?
24. What is 0.8 × 22?
25. What is 4.3 × 13?
26. What is 2.9 × 16?
27. What is 1.4 × 18?
28. What is 5.1 × 11?
29. What is 0.5 × 24?
30. What is 3.5 × 17?
31. What is 2.8 × 15?
32. What is 1.6 × 14?
33. What is 0.2 × 35?
34. What is 4.6 × 12?
35. What is 0.7 × 20?
36. What is 3.9 × 11?
37. What is 1.3 × 19?
38. What is 2.4 × 13?
39. What is 5.5 × 10?
40. What is 0.6 × 30?

Hard Level (Questions 41-60)

41. What is 3.25 × 12?
42. What is 4.75 × 14?
43. What is 2.85 × 11?
44. What is 1.95 × 15?
45. What is 0.65 × 23?
46. What is 5.12 × 10?
47. What is 3.67 × 12?
48. What is 6.45 × 14?
49. What is 2.54 × 16?
50. What is 0.78 × 19?
51. What is 1.47 × 20?
52. What is 4.83 × 13?
53. What is 3.81 × 11?
54. What is 2.92 × 15?
55. What is 5.67 × 14?
56. What is 1.34 × 18?
57. What is 0.48 × 25?
58. What is 7.21 × 12?
59. What is 2.39 × 16?
60. What is 4.28 × 14?

Answers

Easy Level Answers

1. 5.5
2. 12.0
3. 40.8
4. 20.0
5. 42.0
6. 58.5
7. 8.4
8. 22.5
9. 32.0
10. 16.2
11. 36.3
12. 18.0
13. 26.4
14. 14.0
15. 56.0
16. 10.0
17. 20.9
18. 25.0
19. 39.0
20. 9.0

Medium Level Answers

21. 36.4
22. 44.4
23. 28.5
24. 17.6
25. 55.9
26. 46.4
27. 25.2
28. 56.1
29. 12.5
30. 59.5
31. 42.0
32. 22.4
33. 7.0
34. 55.2
35. 21.0
36. 42.9
37. 24.7
38. 31.2
39. 55.0
40. 18.0

Hard Level Answers

41. 39.0
42. 66.5
43. 31.35
44. 29.25
45. 14.95
46. 51.2
47. 44.04
48. 90.3
49. 40.64
50. 14.82
51. 29.4
52. 62.79
53. 41.91
54. 43.8
55. 79.38
56. 24.12
57. 12.0
58. 86.52
59. 38.24
60. 59.92

Conclusion

Great work, Year 6! You’ve learned how to multiply decimals by two-digit numbers. Remember to practice these steps and use the tips to help you succeed. Happy calculating!