Multiplying Two Decimals Less Than One | How to Multiply Decimals | Math with Mr. J

[Music] welcome to math with mr j [Music] in this video i'm going to cover how to multiply two decimals that are less than one whole let's jump into our examples starting with number one where we have seven tenths times three hundredths now the first thing that we're going to do we're going to take the decimals out and rewrite this problem vertically so up and down using whole numbers so we're going to rewrite this as 7 times 3. again we're taking the decimals out we will worry about placing the decimal later in our answer now we can multiply seven times three is twenty-one now the answer to seven tenths times three hundredths isn't twenty-one we need to still place our decimal in that answer so we need to think how many digits are to the right of a decimal in the original problem well one two three three digits to the right of a decimal so our answer needs three digits to the right of the decimal so one two three we can put a zero in the tenths place and then we have our decimal and i'll put a 0 in the ones place to show that we do not have any whole numbers here so our final answer is 21 thousandths again three digits behind a decimal in the original problem and three digits behind the decimal in our final answer let's move on to number two where we have 92 hundredths times hundredths so let's take the decimals out and rewrite this vertically 92 times 54. let's multiply starting with 4 times 2 which is 8 and then 4 times 9 which is 36. we're done with this 4. now we need a 0 here because we are moving 1 place to the left 5 times two is ten so we have another zero carry the one and now we have five times nine which is forty-five plus that one is forty-six once we get to this point we can add so eight plus zero is eight six plus zero is six three plus six is nine and then we have a four now we're ready to place the decimal in our answer so we need to take a look at the original problem and see how many digits are to the right of a decimal so one two three four so our answer needs four digits to the right of the decimal 1 2 3 4. so we can place our decimal right here i'll put a 0 in the ones place to show that we do not have any whole numbers our final answer four thousand nine hundred sixty-eight ten thousandths so there you have it there's how you multiply two decimals that are less than one whole i hope that helped thanks so much for watching until next time peace