How do you multiply a decimal?
For exapmple,2.4 times 3.5

1).  Count the total number of decimal places AFTER the decimal pointsin both numbers.  In your example, there's one in the 2.4 and one in the 3.5,for a total of two.  Put that '2' in your pocket for later.2).  Now forget about the decimal points.  Just write the numbers one under the other, and multiply them as usual.           like    24                   x 35                 3).  When you get the answer (like 840), THEN pull out the '2' that you have beensaving in your pocket from before.Starting at the RIGHT side of your answer, count '2' places back from the endand put a decimal point there.Now you have      '  8.40  '.That's the answer to multiplying the decimals.

Multiply the example as you would for two digit numbers, like 24x35=840. Then, add all the numbers behind the missing decimals. In this case it is 2 so count 2 spaces from the right and add the decimal. 2.4x3.5=8.40