So knowing place value makes adding subjects easier?

It just helps you understand what the number actually represents.

Would the same idea work for hundreds?

Yes the same idea should work for hundreds. However if you where to work with monkeys you would have quite a few monkeys on your hand.

at 2:27 and 2:31 in the video, why did sal count 1-8 twice

Sal probably counted 1-8 twice to focus on that part of the problem and help you focus to understand the problem. :)

I know what place value means.....Can anybody tell me what a face value means ?

To take something at face value is an idiom, an expression. It means you believe things are just as they seem. If you take what someone says at face value, it means that you trust what they say. A face value can also be the number face up on a die. It can even be a specific amount of money involved in insurance. Which meaning were you thinking about? How did you encounter the expression?

Main content

Early math review

Course: Early math review > Unit 3

Lesson 1: Teens

Teen numbers: monkeys

Name: Teen numbers: monkeys
Uploaded: 2014-03-24T19:52:21Z
Description: Sal breaks the number 18 into 10 and 8.

Google Classroom

Sal breaks the number 18 into 10 and 8. Created by Sal Khan.

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EzekielTweneboah
Posted 9 years ago. Direct link to EzekielTweneboah's post “So knowing place value ma...”
So knowing place value makes adding subjects easier?
Comment on EzekielTweneboah's post “So knowing place value ma...”
(8 votes)
- SCORP
  Posted 9 years ago. Direct link to SCORP's post “It just helps you underst...”
  It just helps you understand what the number actually represents.
  (2 votes)
Maryam A.K.
Posted 8 years ago. Direct link to Maryam A.K.'s post “Would the same idea work ...”
Would the same idea work for hundreds?
(4 votes)
- Blueberry Erath
  Posted 8 years ago. Direct link to Blueberry Erath's post “Yes the same idea should ...”
  Yes the same idea should work for hundreds. However if you where to work with monkeys you would have quite a few monkeys on your hand.
  Comment on Blueberry Erath's post “Yes the same idea should ...”
  (8 votes)
zacort0738
Posted 7 years ago. Direct link to zacort0738's post “at 2:27 and 2:31 in the v...”
at
2:27
and
2:31
in the video, why did sal count 1-8 twice
(3 votes)
- Angela Thornock
  Posted 7 years ago. Direct link to Angela Thornock's post “Sal probably counted 1-8 ...”
  Sal probably counted 1-8 twice to focus on that part of the problem and help you focus to understand the problem. :)
  (3 votes)
FoxFace
Posted 9 years ago. Direct link to FoxFace's post “I know what place value m...”
I know what place value means.....Can anybody tell me what a face value means ?
(1 vote)
- Inger Hohler
  Posted 8 years ago. Direct link to Inger Hohler's post “To take something at face...”
  To take something at face value is an idiom, an expression. It means you believe things are just as they seem. If you take what someone says at face value, it means that you trust what they say.
  A face value can also be the number face up on a die.
  It can even be a specific amount of money involved in insurance.
  Which meaning were you thinking about? How did you encounter the expression?
  Comment on Inger Hohler's post “To take something at face...”
  (4 votes)
THEONLYDANC
Posted 4 hours ago. Direct link to THEONLYDANC's post “i think ur the only one t...”
i think ur the only one teaching us
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(1 vote)
Answer

Video transcript

Voiceover:Let's say that you're throwing a party, and as we all know, any party needs a sufficient number of monkeys. Right now you have 10 monkeys. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10. But you would like to have 18 monkeys. How many more monkeys do you need in order to have 18 monkeys? I encourage you to pause the video and think about it on your own before I work through it. Remember, the goal here is to get to ... The goal here ... Let me write it this way. The goal here is to get to 18, 18 monkeys. Now what do we know about the number 18? Well the number 18, you have this 1 right over here in the tens place. That literally represents 1, 10. And then this 8 represents 8, 1's. Plus 8, 1's. That's the same thing as saying 1, 10 ... 1, 10, that's just a 10 right over there. And 8, 1's, that's just 8. 18 is the same thing as 10 plus 8. If we start with 10 monkeys, which is how many we have started with, how many more do we need to get to 18? Well, if you start at 10, you need 8 more to get to 18. We can verify that visually, if we like. Let's see. Let me copy and paste 1 of these monkeys. Copy. This is 10. Now, let's get to 18. 11, 12, 12, 13, 14, 15, 16, 17, and 18. And 18. How many more did we add? Well, once again, we started, we started with this 10 right over here. Let me box them off. We started with these 10 monkeys. That's 1 group of 10 right over there. We started with the 10. And then we added 8 more monkeys. 1, 2, 3, 4, 5, 6, 7, 8. 1, 2, 3, 4, 5, 6, 7, 8. So we started with 10. We added 8 more monkeys. We added 8 more monkeys to get, to get to 18. And once again, how did we first think about that? Well, 18 is 1, 10 plus 8, 1's. Or 10 plus 8.