Decimal Multiplication

Decimal Multiplication:

To multiply decimals:

  1. Write the numbers vertically (you don't have to line up the decimal points in the numbers).
  2. Multiply the numbers together as if they were whole numbers.
  3. Count the number of digits to the right of the decimal point in the top number.
  4. Count the number of digits to the right of the decimal point in the bottom number.
  5. Add the 2 counts together.
  6. Place the decimal point in the answer that number of digits from the right.

The following are examples of multiplying decimals.

Multiplying Decimals
  Write the numbers vertically.   Multiply the numbers together Count digit right of the decimal points. Add the counts together and place the decimal point in the answer.
12 x 2.3
12
x 2.3
12
x 2.3
36
240
276
12
x 2.31
36
240
276
12
x 2.31
36
240
27.61
23.3 x 2.4
23.3
x 2.4
23.3
x 2.4
932
4660
5592
23.31
x 2.41
932
4660
5592
23.31
x 2.41
932
4660
55.922
0.123 x 16
0.123
x 16
0.123
x 16
738
1230
1968
0.1233
x 16
738
1230
1968
0.1233
x 16
738
1230
1.9683
0.51 x 0.12
0.51
x 0.12
0.51
x 0.12
102
510
612
0.512
x 0.122
102
510
612
0.512
x 0.122
102
510
0.06124

Check Your Understanding

  1. Enter two numbers between 0 and 999.999.
  2. Think of what you believe the answer should be.
  3. Click the button "Check" and check your answer.
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