How do you figure out where to put the decimal when multiplying decimals???

Help please?How do you figure out where to put the decimal when multiplying decimals???
ignore the decimals when u originally do the problem, then however many deciams there are in both of the decimals you're multiplying is how many there will b in the answer. i.e. if you multiply 6.78x4.234 together the answer will have 5 numbers behidnthe dceimal pointHow do you figure out where to put the decimal when multiplying decimals???
When you multiply decimals, you move the decimal to the left however many total decimal places that were in the factors.





For instance...





0.25 * 0.3 = 0.075





There are 2 decimal places in 0.25 and 1 decimal place in 0.3, so the product will move the decimal over 3 places.
However many numbers the two numbers have after the decimal place is how many timems you move the decimal to the left.


e.g.


1.2


1.2(both added are 2numbers after decimals)


-----


24


120


-------


1.44
You count the # of decimal places from the numbers being multiplied. For example:





2.11 (notice that if you start from the right, there's 2 places until you get to the decimal) x 3.456 (notice that if you start from the right, there's 3 places until you get to the decimal) = 7.29216





Notice that for the answer 7.29216 the decimal place is 5 places from the right since it was 2 places + 3 places = 5 places.





Clear as mud?
3.2 X 5 = 16.0 3.4 X 2 = 6.8 You multiply as you would any numbers , forgetting about the decimals, and then when you get the answer, you look at how many numbers follow the decimal in the two numbers you multiplied, and that is how many places from the right you put your decimal in the anwer. Ex:


3.4


X


5.7


-------


238


170


--------


1938 But you see that there were two numbers after decimals in the problem ( .4 and .7) So you have to count two spaces from the right in the answer, which makes the answer


19.38 and not 1938. I hope this helps.
When multiplying decimals, don't consider decimal places until the problem is solved. Count all places to the right of the decimal point in the problem. which is 5. Count that number of places in the product (the answer) starting from the right.





example





0.004


x 0.02


= 0.00008
ignore the decimals then count how many spaces are behind the decimals on both numbers (after you do the problem) and put that many spaces in the product
by counting how many numbers are after the decimals. Like if you do .2 * .3 you have two numbers that are after the decimal so your answer if .06. So with every one number you have after the decimal move the decimal to the left by one.
Multiply like you would with two whole numbers, but then move the decimal point to the left once for each number to the right of the decimal point in either of the factors. For example:





1.1 X 2.22


11 X 222 = 2442


3 total digits to the right of decimal point (.1, .22), so:


2.442
Let me show you by example:


8.15


x 4.2


-------------





when you multiply the problem above, you have the number: 34230


to figure out where you put the decimal, you count the number of decimal spaces in the problem. 8.15 has 2 decimal spaces, 4.2 has 1 decimal space. You add them together to get 3, and that is how many decimal spaces will be in the result. You get the number: 34.230, or, 34.23





hope I could help!
when multiplying decimals, set up the problem like this (as an example):





.45


x .13


---------





then, multiply as normal, ignoring the decimals, and youll find the answer (w/o decimals) is:


135


+ 450


=585


you move the decimal point over 4 space, so the answer is: 0.0585 (the 0 after the decimal point is used as a filler so that you can move the decimal over 4 space). the reason you move it over the number of spaces you do has to do with the placement of the decimal points in the original equation. because the equation was .45 x .13, you have to move the decimal pt in the answer over 4 spaces, because in .45, the decimal is moved over 2 spaces from the end of the number (45), PLUS in .13 the decimal is moved over 2 spaces from the end of the number (13), and 2 PLUS 2 equals 4.





if the example had been .45 times .1, i would move it over only THREE spaces in the answer, because in .45 and .1, the decimal is moved over two places in .45 and only ONE place in .1, making a total of 3 place movements. get it?
Multiply normally, then count the number of places after each decimal point in the numbers and count from the right to left in your answer...........so 0.06 times 0.4 = 0.024
okay now write the problem without the decimals then at the end when you finish multiplying then take and ask how many numbers are behind the decimal and move the decimal in your answer to get your decimal answer
it stay where it was just add the for example .. 1.5 +0.75 = 2.25
when multiplying just bring it strait down