How do you multiply two decimal numbers together?

Pretend there are no decimal points, and multiply the numbers together. Then count over (from the right) the number of decimal points of the two numbers combined.

For example:

3.4 * 0.185 = 0.6290

34 * 185 = 6290. There is one number to the right of the decimal point in 3.4, and three to the right in 0.185. One plus three is four, so starting from 6290. you move over four places.