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## Arithmetic (all content)

### Course: Arithmetic (all content) > Unit 2

Lesson 2: Making 10# Adding to 10

Sal finds out how many bananas we need to add to 3 bananas to make 10 bananas. Created by Sal Khan.

## Want to join the conversation?

- Do you have to add only numbers? Or can you add real bananas too?(26 votes)
- You can add anything. Bananas can each represent a number.(9 votes)

- If 3 + 7 = 10 then what is the missing number in 235 + ___ = 1,000?(11 votes)
- You can reverse the equation into 1000-235=?

And the answer is 765.

I hope you didn’t get this question from your HW.(8 votes)

- you can use your fingers(12 votes)
- Yes, you can use anything as long as what you are using has the proper increments in the numerical increment where you are calculating the quantity of the equation.(3 votes)

- i like math so much becusea it fun to to do and you can yous your fingers or number line(9 votes)
- why do we have to watch these videos if we alredy know it?(3 votes)
- Because It is good for you to refresh your memory on the topic.(4 votes)

- what is 7 to the 2nd power plus three divided by 6 times 2(3 votes)
- 1.44444444444444444444444444444444444444444444444444444... etc.(3 votes)

- why do y'all need to show the video(3 votes)
- You can also subtract 10 from 3 to get the answer(2 votes)
- If you take 10 from 3 you get -7 because if you want a positive # (number without the minus sign in front of it) you have to take 3 away from 10 that is how you get 7(5 votes)

- how i add 5 to 10(2 votes)
- Hey there.

Grab some objects (pencils, for example). Count out 5 of them, and put them in a pile. Then count out 10, and put them in another pile. Then put the two piles together and count the amount of pencils in the combined pile. You should get 15.(4 votes)

- Can you turn around facts like 3+4=7; 4+3=7?(2 votes)
- Yes! You sure can, if you have the same numbers it would turn out to be the same answer.(1 vote)

## Video transcript

- [Voiceover] We've
got three bananas here. One, two, three. So I'm starting with three bananas and I want to add some number of bananas so that I end up with 10 bananas. So this is what I'm starting with. I'm starting with three and I want to end up with 10. One, two, three, four, five, six, seven, eight, nine, ten. So what do I have to add to the three to get to 10? I encourage you to pause this video and try this out on your own. So let's work through this. So let's just start adding bananas. So that's three. So now let me add a fourth. That would be my fourth banana. Five bananas. Six bananas. Seven bananas. Eight bananas. Nine bananas. And ten bananas. So how many bananas did I add? So now I added some
number of bananas here. So in total I have one,
two, three, four, five, six, seven, eight, nine, ten. So how many did I have to add to the three in order to get to the total of 10 in order to get this 10 right over here? We could just count these. This is one, this is two, this is three, four, five, six, seven. I added seven bananas. I added seven bananas to
the original three bananas to get to 10. So three plus seven is equal to 10. And you can see that what
we have on this left side is indeed equal to what
we have on the right side. On the left side we have
one, two, three, four, five, six, seven, eight, nine, ten bananas and on the right hand side
we have one, two, three, four, five, six, seven, eight, nine, ten. So they are indeed equal.