1 00:00:00,000 --> 00:00:00,570 2 00:00:00,570 --> 00:00:03,500 Let's tackle a slightly more interesting division problem. 3 00:00:03,500 --> 00:00:06,606 So we're going to take 280 and divide it by 5. 4 00:00:06,606 --> 00:00:08,230 And I encourage you to pause this video 5 00:00:08,230 --> 00:00:09,760 and try to apply the technique that we've 6 00:00:09,760 --> 00:00:11,634 seen in a previous video to try to figure out 7 00:00:11,634 --> 00:00:14,630 what 280 divided by 5 is. 8 00:00:14,630 --> 00:00:15,890 So let's have our go at it. 9 00:00:15,890 --> 00:00:16,970 So we could rewrite this. 10 00:00:16,970 --> 00:00:24,390 We've already seen this as 280 divided by 5. 11 00:00:24,390 --> 00:00:26,200 So the first question we can ask ourselves 12 00:00:26,200 --> 00:00:28,300 is, how many times does 5 go into 2? 13 00:00:28,300 --> 00:00:30,360 Well, 5 doesn't go into 2 at all. 14 00:00:30,360 --> 00:00:31,845 It goes 0 times. 15 00:00:31,845 --> 00:00:35,590 0 times 5 is 0. 16 00:00:35,590 --> 00:00:36,940 And then we subtract. 17 00:00:36,940 --> 00:00:39,220 2 minus 0 is 2. 18 00:00:39,220 --> 00:00:41,390 And now, we can bring down the next digit, 19 00:00:41,390 --> 00:00:44,139 which, in this case, is an 8. 20 00:00:44,139 --> 00:00:45,930 And so we can ask ourselves, how many times 21 00:00:45,930 --> 00:00:49,570 does 5 go into 28 without going over it? 22 00:00:49,570 --> 00:00:54,450 So we could think, well, let's see 5 times 5 is 25. 23 00:00:54,450 --> 00:00:58,770 5 times 6 is 30. 24 00:00:58,770 --> 00:01:01,150 So 5 times 6 would go over 28. 25 00:01:01,150 --> 00:01:03,760 So we want to go back to 5 times 5. 26 00:01:03,760 --> 00:01:06,630 So 5 goes into 28 5 times. 27 00:01:06,630 --> 00:01:09,280 5 times 5 is 25. 28 00:01:09,280 --> 00:01:11,340 And you subtract. 29 00:01:11,340 --> 00:01:13,490 28 minus 25 is 3. 30 00:01:13,490 --> 00:01:15,710 And now, let's bring down the next digit. 31 00:01:15,710 --> 00:01:18,360 In this case, the digit is a 0. 32 00:01:18,360 --> 00:01:20,290 So how many times does 5 go into 30? 33 00:01:20,290 --> 00:01:21,830 Well, it goes exactly 6 times. 34 00:01:21,830 --> 00:01:23,520 We've already talked about that. 35 00:01:23,520 --> 00:01:26,110 6 times 5 is 30. 36 00:01:26,110 --> 00:01:27,350 We subtract. 37 00:01:27,350 --> 00:01:30,260 And we have nothing left over. 38 00:01:30,260 --> 00:01:37,830 So we just figured out that 280 divided by 5 is equal to 56. 39 00:01:37,830 --> 00:01:39,989 Now, why did this work? 40 00:01:39,989 --> 00:01:41,780 Well, the first way to think about it, this 41 00:01:41,780 --> 00:01:42,606 was actually 200. 42 00:01:42,606 --> 00:01:43,980 And we were thinking about, do we 43 00:01:43,980 --> 00:01:46,080 put anything in the hundreds place here? 44 00:01:46,080 --> 00:01:49,020 So one way of thinking about it, how many hundreds of times 45 00:01:49,020 --> 00:01:52,175 does 5 go into 200? 46 00:01:52,175 --> 00:01:53,800 And it doesn't go any multiples of 100. 47 00:01:53,800 --> 00:01:54,930 And if that's a little confusing, 48 00:01:54,930 --> 00:01:56,140 don't worry too much about it. 49 00:01:56,140 --> 00:01:57,681 But I want you to really think deeply 50 00:01:57,681 --> 00:01:59,190 about the place notation. 51 00:01:59,190 --> 00:02:00,860 But then we were able to, again, extend 52 00:02:00,860 --> 00:02:04,170 it to instead of just 200 but then 280. 53 00:02:04,170 --> 00:02:06,150 This 28 right over here, if you think about it, 54 00:02:06,150 --> 00:02:08,020 this 2 is in the hundreds place. 55 00:02:08,020 --> 00:02:09,710 This 8 is in the tens place. 56 00:02:09,710 --> 00:02:12,030 So this is really representing 280. 57 00:02:12,030 --> 00:02:15,340 And we said, how many tens of times does 5 go into 280? 58 00:02:15,340 --> 00:02:19,220 Well, it goes 5 tens times, or it goes 50 times. 59 00:02:19,220 --> 00:02:22,220 50 times 5 is 250. 60 00:02:22,220 --> 00:02:26,340 When you subtract 250 from 280, you've got 30. 61 00:02:26,340 --> 00:02:28,590 And there were no other things in the ones place here. 62 00:02:28,590 --> 00:02:30,423 So we just have to figure out how many times 63 00:02:30,423 --> 00:02:31,990 does 5 go into 30. 64 00:02:31,990 --> 00:02:33,590 So hopefully, that gives you a sense 65 00:02:33,590 --> 00:02:36,860 of what's actually happening behind this little process. 66 00:02:36,860 --> 00:02:38,070 It's not just magic. 67 00:02:38,070 --> 00:02:41,194 We're really just keeping track of place value here. 68 00:02:41,194 --> 00:02:42,610 The other thing I want to show you 69 00:02:42,610 --> 00:02:45,629 is that we didn't necessarily have to write this 0 here. 70 00:02:45,629 --> 00:02:47,170 Another way of computing it, we could 71 00:02:47,170 --> 00:02:52,465 have said 280 divided by 5. 72 00:02:52,465 --> 00:02:55,080 And we could've said, how many times does 5 go into 2? 73 00:02:55,080 --> 00:02:56,330 Well, it doesn't go any times. 74 00:02:56,330 --> 00:03:00,140 So let's just think about 5 going into 28. 75 00:03:00,140 --> 00:03:03,330 Well, 5 goes into 28 5 times. 76 00:03:03,330 --> 00:03:05,820 5 times 5 is 25. 77 00:03:05,820 --> 00:03:07,020 Subtract. 78 00:03:07,020 --> 00:03:09,310 28 minus 25 is 3. 79 00:03:09,310 --> 00:03:11,190 Bring down the 0. 80 00:03:11,190 --> 00:03:13,690 5 goes into 30 six times. 81 00:03:13,690 --> 00:03:15,630 6 times 5 is 30. 82 00:03:15,630 --> 00:03:17,330 And we have nothing left over. 83 00:03:17,330 --> 00:03:19,580 And again, what we're really saying 84 00:03:19,580 --> 00:03:24,282 is that 5 doesn't go into 200 any hundreds of times. 85 00:03:24,282 --> 00:03:25,865 If this was a 500, you could say, hey, 86 00:03:25,865 --> 00:03:27,660 it's going to go in it 100 times. 87 00:03:27,660 --> 00:03:30,600 But instead, we go, well, what about 5 going into 280? 88 00:03:30,600 --> 00:03:32,080 Well, it goes 50 times. 89 00:03:32,080 --> 00:03:34,400 50 times 5 is 250. 90 00:03:34,400 --> 00:03:36,880 280 minus 250 is 30. 91 00:03:36,880 --> 00:03:38,870 5 goes into 30 six times. 92 00:03:38,870 --> 00:03:41,644 So hopefully, that makes a little bit of sense. 93 00:03:41,644 --> 00:03:42,144