1) To multiply decimals, first estimate the answer without decimals to check the magnitude. Then remove the decimal points from the numbers and multiply them as whole numbers. 2) Partition both numbers into place values and multiply them using the grid method. 3) Replace the decimal point in the final answer by counting the original number of decimal places in the factors.

1. Multiplying
decimals

2. 1
Estimate your
answer
e.g. 24.6 x 39.5
approximately 25 x 40 = 1000

3. 2
Remove the
decimal point
e.g. 24.6 x 39.5
becomes 246 x 395

4. 3
Partition each
number
246 x 395
(200+40+6) x (300+90+5)

5. 4
Multiply using the
grid method
X 300 90 5
200 60 000 18 000 1 000 79 000
40 12 000 3 600 200 15 800
+ 2 370
6 1 800 540 30
97 170

6. 5
Replace the
decimal point
Estimate = 1000
So 97170 becomes 971.70