in this video we're going to focus on long multiplication it's one of those math techniques that you've learned in school let's start with a simple example what is 39 times 8 but what we need to do is multiply eight by nine first eight times nine is seventy two so we're going to write the two and then carry over the seven next we need to multiply eight times three eight times three is twenty four and then you need to add seven to twenty four twenty four plus seven is thirty one so the answer for this example is three 12. let's try another example what is 56 times 9 go ahead and try that one so we have 9 times 6 which is 54 so we're going to write the 4 first carry the 5 and then 9 times 5 is 45 plus the 5 that's 50. so the answer for this example is 504 now let's try an example that is a little bit harder let's multiply 46 by 27 if you want to try it yourself feel free to pause the video and work on it so let's begin by multiplying seven by six seven times six is forty-two so we're gonna write the two carry over the four next we have seven times four which is 28 and then we need to add 4 to 28 so 28 plus 4 is 32 next we're going to multiply 6 times 2 which is 12. oh before we do that by the way we need to write a zero and then we can multiply six times two which is twelve we'll write the two and then carry over the one next we have two times four which is eight and then plus one that's nine so now we need to add these two numbers two plus zero is two two plus two is four three plus nine is twelve so the answer is one thousand two hundred and forty two now if you were confused by that example let me give you another one that's similar for the sake of practice you can try it let's multiply 76 by 52 so we're going to start with 2 times 6 2 times six is twelve let's write the two first and then carry over the one and then two times seven is fourteen plus one that's fifteen now let's write a zero five times six is thirty so we're going to write a zero carry over the three and then five times seven is 35 plus three that's 38 and now we need to add so this is going to be 2 5 8 plus 1 is 9 and then we have a 3. so it's 3 952 that's the answer let's try a more challenging example let's multiply 369 by 43 go ahead and work on that so we have 3 times 9 which is 27 so we'll write the 7 carry over the 2. three times six is eighteen plus two that's twenty so we'll write the zero carry over the two three times three is nine plus two that's eleven now let's add a zero and then we have four times nine which is 36 we'll carry the three four times six is 24 plus three that's going to be 27 carry over the two 4 times 3 is 12 plus 2 that's 14. so now we need to add so we have 7 6 1 plus 7 is 8 1 plus 4 is 5. and so the answer is going to be 15 867. so this is going to be the final example it's going to be the hardest one that we've worked on in this video multiply 759 by 438 so first we have eight times seven i mean a times nine rather eight times nine is seventy two write the two and then carry over the seven next is eight times five eight times five is forty add seven that's forty seven so we're going to write the seven carry over the four and then eight times seven is fifty six plus four that's 60. now add a zero 3 times 9 is 27 so write the 7 carry the 2 3 times 5 is 15 plus 2 that's 17. so let's write the 7 carry the 1 and then 3 times 7 is 21 plus 1 that's 22. now we're going to write two zeros instead of one before we go into uh the fours so four times nine is thirty six let's carry over the three four times five is twenty plus three that's twenty three let's write the three and then carry over the two four times seven is 28 plus two that's 30. so we're just going to write 30 at this point and now we can add so we have 2 and then 7 plus 7 is 14. we need to write the four carry the one and then we have one plus seven plus six one plus seven is eight a plus six is fourteen so let's write four carry over the one then we have one plus six which is seven seven plus three is ten ten plus two that's twelve and then two plus one is three and then we can write the other three so the final answer is three hundred thirty-two thousand four hundred and forty-two so now you know how to multiply two numbers using long multiplication