Multiplying Decimals Worksheets - Math Monks - Free Printable

Let’s solve each multiplication problem step by step. We’ll multiply the numbers as if they were whole numbers first, then count the total decimal places in both numbers and put the decimal point in the answer accordingly.

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Problem 1: 5.8 × 13

Step 1: Ignore decimals → 58 × 13
58 × 10 = 580
58 × 3 = 174
580 + 174 = 754

Step 2: Count decimal places → 5.8 has 1 decimal place, 13 has 0 → total = 1

Step 3: Put decimal back → 75.4

✔ Answer: 75.4

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Problem 2: 6.78 × 0.93

Step 1: Ignore decimals → 678 × 93
First, 678 × 90 = 61,020
Then, 678 × 3 = 2,034
Add them: 61,020 + 2,034 = 63,054

Step 2: Decimal places → 6.78 has 2, 0.93 has 2 → total = 4

Step 3: Put decimal back → 6.3054 (count 4 digits from right)

✔ Answer: 6.3054

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Problem 3: 108.73 × 2.18

Step 1: Ignore decimals → 10873 × 218
Break it down:

10873 × 200 = 2,174,600
10873 × 10 = 108,730
10873 × 8 = 86,984

Now add:
2,174,600
+ 108,730 = 2,283,330
+ 86,984 = 2,370,314

Step 2: Decimal places → 108.73 has 2, 2.18 has 2 → total = 4

Step 3: Put decimal back → 237.0314

✔ Answer: 237.0314

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Problem 4: 496.2 × 3.82

Step 1: Ignore decimals → 4962 × 382

Break it down:

4962 × 300 = 1,488,600
4962 × 80 = 396,960
4962 × 2 = 9,924

Add:
1,488,600
+ 396,960 = 1,885,560
+ 9,924 = 1,895,484

Step 2: Decimal places → 496.2 has 1, 3.82 has 2 → total = 3

Step 3: Put decimal back → 1895.484

✔ Answer: 1895.484

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Problem 5: 786.27 × 3.3

Step 1: Ignore decimals → 78627 × 33

78627 × 30 = 2,358,810
78627 × 3 = 235,881
Add: 2,358,810 + 235,881 = 2,594,691

Step 2: Decimal places → 786.27 has 2, 3.3 has 1 → total = 3

Step 3: Put decimal back → 2594.691

✔ Answer: 2594.691

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Problem 6: 999.9 × 7.7

Step 1: Ignore decimals → 9999 × 77

9999 × 70 = 699,930
9999 × 7 = 69,993
Add: 699,930 + 69,993 = 769,923

Step 2: Decimal places → 999.9 has 1, 7.7 has 1 → total = 2

Step 3: Put decimal back → 7699.23

✔ Answer: 7699.23

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Problem 7: 128.3 × 2.2

Step 1: Ignore decimals → 1283 × 22

1283 × 20 = 25,660
1283 × 2 = 2,566
Add: 25,660 + 2,566 = 28,226

Step 2: Decimal places → 128.3 has 1, 2.2 has 1 → total = 2

Step 3: Put decimal back → 282.26

✔ Answer: 282.26

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Problem 8: 9.8 × 13.8

Step 1: Ignore decimals → 98 × 138

98 × 100 = 9,800
98 × 30 = 2,940
98 × 8 = 784
Add: 9,800 + 2,940 = 12,740 + 784 = 13,524

Step 2: Decimal places → 9.8 has 1, 13.8 has 1 → total = 2

Step 3: Put decimal back → 135.24

✔ Answer: 135.24

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Problem 9: 155.72 × 22.7

Step 1: Ignore decimals → 15572 × 227

Break it down:

15572 × 200 = 3,114,400
15572 × 20 = 311,440
15572 × 7 = 109,004

Add:
3,114,400
+ 311,440 = 3,425,840
+ 109,004 = 3,534,844

Step 2: Decimal places → 155.72 has 2, 22.7 has 1 → total = 3

Step 3: Put decimal back → 3534.844

✔ Answer: 3534.844

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Final Answer:
1. 75.4
2. 6.3054
3. 237.0314
4. 1895.484
5. 2594.691
6. 7699.23
7. 282.26
8. 135.24
9. 3534.844