How do you multiply decimals?

Answer 1

1.2
x .09
---------

multiply 9 times 12

108

then count the number of places behind the decimals (top and bottom number)
there're 3 so you have that same number of places behind the decimal so you get:

.108

Answer 2

When multiplying decimals by hand, go ahead and ignore the decimal point during the multiplication process. It comes in later, once you have a number result. Total the number of digits to the right of the decimal place, then place the decimal in the answer to have that many total digits to the right, as well.

Let's multiply 3.5 x 1.3.

35 x 13 is 455, so that's easy enough. But where to put the decimal point?

Well, in the original problem, there are two numbers to the right of the decimal: in 3.5 and 1.3, there are a .5 and a .3.
So we move the decimal point in "455" two places to the left, giving us "4.55" as the answer.

How about 3.51 and 1.32?

351 x 132 = 46332.

3.51 has two numbers to the right of the decimal, and 1.32 also has two numbers to the right of the decimal... so 46332 needs to have four total numbers to the right, as well. Moving the decimal four places to the left gives us: "4.6332" as the answer to our example.

Answer 3

You line the decimals up and do the math then add how many spaces are to the right of the decimals and put it in the answer

Answer 4

multiply the numbers as if there were no decimals
Then add up all the decimal places from the two numbers
and shift the decimal left the same number of places.

eg.
1.2 x 2.34
12x234=2808
1.2 has 1 dec place, 2.34 has 2 total - 3
so the product = 2.808

Answer 5

2.04 (2 places to right of .)
x 3.5 (1 place to right of .)

1020
612

62220
62.220 (2+1=3 places to right of .)
***

Answer 6

With a calculator if you please!