When multiplying decimals, first multiply the numbers together, then add up the number of decimal places shifted from to the left.
For example, , if we multiply , we get 120. The decimal shift in total is 1. So the answer is 12
Another example, , if we multiply , we get 144. The decimal shift in total is . So the answer is 1.44
When dividing decimals, multiply the top and bottom by sets of 10 until there are no decimal places left.
For example, , multiply both top and bottom by 10. The answer is therefore .