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# Adding 1 vs. adding 10

Sal talks about the difference between adding 1 and adding 10.

## Want to join the conversation?

- At0:35, what does Sal mean by "one's place?"(12 votes)
- It is the smallest place. It comes last in a number. For example, in 234 the number in the ones place in 4.(0 votes)

- what if your adding something 12+19?(3 votes)
- First, you add the ones, 9+2=11. You next add the tens, 10+10=20. 11+20=31.(5 votes)

- Is a great time to ale the only thing is that what we need to get to know you have a great day for you and your family and friends with you on your phone number is on the us and the fact that you have to go to them and i will try and get back to me that the only thing is i just wanted to let you know when you want me in the future of the day after that time ⌚(1 vote)
- what if your adding 12+19(1 vote)
- For information 12 plus 19 is 31(0 votes)

## Video transcript

- [Voiceover] So, pause this video and, real quick, figure out what 27 plus 1 is, and then, if possible, figure out what 27 plus 10 is. Alright, so, let's think about it together. So, you might've been able to do this one pretty easily. You might've said, "Okay! If I'm adding 1, "it's just going to be the next highest number from 27. "I would go to 28 if I have 1 more." But, the reason why I'm doing this exercise is, we really think about place value. So, over here, the number 27, we have a 2 in the ten's place, this is in the ten's place, right over here, and then we have a 7 in the one's place. So, you could visualize the number 27 as 2 tens, and I have 2 groups of 10 here, and then 7 ones, and I have 7 ones right over here. And then, if I add 1 more, that's 1 more of these individual ones, and so, what am I going to be left with? Well, I'm still going to have 2 tens, I'm still going to have 2 tens, but how many ones am I going to have now? Oh, 1, 2, 3, 4, 5, 6, 7, 8 ones. So, it's going to be 28. So, that might not be surprising for you, but it's really valuable to think about in terms of place value because it can be very useful later on as you learn more math. Now, let's do the same thing with 27 plus 10. We already said 27, that's 2 tens and 7 ones, and now, with 10, the 1 isn't in the one's place, so it doesn't just represent 1, the 1 here is in the ten's place, so we have 1 10 and we have 0 ones. So, we just have-- The number 10 is just a group of 10 here! So, when you add these together, what are you going to have? Well, now, you're going to have 1, 2, 3 tens, you're going to have 3 in the ten's place, and you're still going to have 1, 2, 3, 4, 5, 6, 7 ones. 7 ones. So, notice. Here, when you added a 1, you increased your one's place by 1. And, here, when you added 10, which is really 1 10, you didn't increase the one's place, you increased the ten's place.