How to Divide Three Digits by TwoBy Bon Crowder
Dividing three digits by two doesn't require the use of a calculator if you know what you're doing. Divide three digits by two with help from an experienced math professional in this free video clip.
How to divide 3 digits by 2. My name is Bon Crowder, and I'm with MathFour.com, and I'm here to talk about dividing 3 digits by 2 digits. So we have an example here 638 divided by 27 and I'm going to divide these by doing 27 into 638. So the way we do this is we cover up the digits except for the first and the first and we go okay, how many times does 2 go into 6 because that's going to be our first guess, 2 goes into 6 three times so I'm going to guess that 27 goes into 63 three times. That's my first guess. So then I multiply 3 x 7 is 21 and 3 x 2 is 6 + 2 is 8 and when I try to subtract I go, oh my goodness, it's too big. So then I'm going to have to go back so I erase that piece and I erase my little 3 and I go down 1. So instead of 3 I go to 2, get rid of him, 2 x 7 is 14, carry the 1, 2 x 2 is 4 +1 is 5 and then when I go to subtract, aha, now I can do this, 63 - 54 is 9 and then I bring down the 8. I played the same game. I cover up the 7 and the 8 and consider only the 2 and the 9. How many times does 2 go into 9. Well, 2 x 4 is 8 so 2 goes into 9 four times, that's our guess, 4 x 7 is 28, hey look the 8s match, get rid of that, carry the 2, 4 x 2 is 8, 9, 10, bust, that's not going to work. So I have to erase the 4 and get rid of this 108 and I have to go down 1, so I go to 3, 3 x 7 is 21, I've got a lot of carries over here, 3 x 2 is 6, 7, 8, aha, that I can subtract, 8 - 1 is 7, 9 - 8 is 1 so I have 23 remainder 17. And that's how you divide a 3 digit number by 2. I'm Bon Crowder with MathFour.com. Have fun.