I need to know how to set up a multiplication problem using zeros on the end of the second row of numbers. I'll try to put one on here and see if it works. My husband and I have differing methods of writing it out, and we don't know which way is 'proper'. The top numbers let's say are 456 and the bottom number is 30. I think the 3 goes under the 6 and the 0 is 'dropped' at the end. He says the 3 goes under the 5 and the 0 under the 6. Does it matter or not? I am just thinking this could cause problems for the kids later on so I want to do it right! Help pretty please!
I do it the same way as your husband does - it makes sure that they don't FORGET about that zero sitting there
Ok I think I should clarify, by 'dropping' the zero I didn't mean that it isn't written, I mean that when you figure the problem it is simply written at the end and nothing else is done with it. then you would move to the next number, in this case 3. ugh, I hate math?! I never made it past 5th grade math to be honest. Math makes as much sense to me as all those wires and thingies under the hood of my car lol
I was always taught to (and still do) put the 3 under the 5 so that way you don't forget about the 0. I would definitely forget. And don't feel bad, I'm in the same "math boat" as you are, lol.
kind of confused as to what you mean so i'll just write out the problem step by step and see if that helps 456 30 ____ multiply 456 by zero 000 multiply 456 by 30 (or 456 by 3 and add a zero to the end... 456 by 30 is more or less for doing it in your head, & what i mean by that is if it was originaly 35 * 456 you would do 5 * 456 + 30 * 456, but in any case the reason that you add a zero to the right when you're in the tens is that you really aren't just multiplying it by 3, you're multiplying it by 30... which they never taught us in school) 13,680 now add em up: 000 13680 _______ 13680 hope that answered whatever your problem was. I'm thinking maybe you meant do you even add the line of zeros, but you do that so that you remember to add another zero on the next line... because it can get really confusing if you have a 6 digit number and you just didnt add the first line of zeros so maybe you notice that you're putting the 4th line of addition on so you just figure add 3 zeros, but really you should add 4 because if you added that first line in then the 4th line down would be the 5th line. or even worse if the line of zeros was going to be in the 10s or 100s place and you didnt add it. in any case you don't HAVE to add the line of zeros, but if you don't you better keep track if you're in the 10s or 100s or 1000s place etc., and i doubt kids just learning multiplication do that too well
I LEARNED your husband's way. But I DO it YOUR way. I would teach my child the appropriate way....but when old enough I'd teach them the "trick". I didn't learn it until college Algebra, actually! TT Grade 5 teaches the dropping the 0, actually.
Ok, well it looks as it the line of 0's is the right way then? that just blows my mind, why on earth would I teach my kid to X everything X zero just to end up with a bunch of 0's ?! I will have to sit down and look that over, because it is quite confusing to me
okay Im gonna have to read through this one cause it sounds confusing, you write it the same way you would ay other problem ?? DUH? lol, thats my opinion , but 365X30 woudl be written as such up or sideways, you put the 3 under the 6 and the 0 under the 5, and dont be missing writting in the 0 as a space holder or your kids will start missing numbers or getting the adding off.
I agree with kbabe. Most people learn your husband's way, but it's easier your way. The "right" way is whatever way is right for the person solving the problem
If you're going to teach it to your kids, teach it your husband's way. The reason is that lining it up his way respects place value. You put the ones in the right-most column, then the tens and so on. Your way seems easy but it relies on memorization rather then understanding what's actually happening with place value and may lead a younger person who's less sure of their math skills down the wrong path in understanding the algorithm.
I put the zero sticking out one place to the right, so the 3 is under the 5. Then just write the zero under the zero, and go ahead and multiply by 3. No sense in "zero times 6 is zero, zero times 5 is zero, zero times 4 is zero" -- all that effort and you've still got nothing! I forget what grade they taught us that when I was in school - probably about 5th or 6th.
Jackie, I agree with you. Once the concept is taught that way, you can teach the "trick" later, maybe in 4th or 5th grade.
I learned to multiply your husband's way, when in school. I taught my children both ways. Husband's way first and then your way. One of my children had trouble multiplying by 0. Once I showed her how to multiply w/ the 0 dangling, lightbulb went off and no more problems!! Oh yeah.....Saxon teaches it your way in I believe either Saxon 6/7 or Saxon 7/8. LR
ya know my dd had to explain the reasoning in the 0 to the side, that is just really confusing to me I would not teach my kids it .. what will they do when the numbers get bigger, it will be even easier to miss a number... IMHO
