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Course: 1st grade>Unit 1

Lesson 1: Numbers 0 to 120

Missing numbers between 0 and 120

Sal finds missing numbers between 0 and 120.

Want to join the conversation?

• At , Numbers go on and on towards infinity. Is this true?
(9 votes)
• Yes Numbers can go on forever until infinity. There is no 'end number' in all of the numbers.
(3 votes)
• How big can the number grid go? Is there a maximum size?
(2 votes)
• Nope, numbers (and number grids) can go on forever!
(6 votes)
• Are there any numbers between two numbers or are there only those numbers I know?
(0 votes)
• There are infinite numbers of decimals between to numbers that are not the same. between 1 and 2 there is 1.0, 1.01, 1.02, 1.001, 1.002 and so on.

Hope that helps!
(4 votes)
• Do you say "one hundred and one" or do you say "one hundred one"?
(2 votes)
• You should say "one hundred one" because "one hundred AND one" is reserved for reading decimals. watch Khan's/Sal's videos about decimals.
(1 vote)
• Is 110 the last number ever?
(0 votes)
• numbers can go on for ever, most people use the term infinite, the symbol for the term infinite is a sidways eight becouse the loop goes on for ever.
(5 votes)

Video transcript

- [Voiceover] What is the missing number, 100, 101, 102, 103, 104, 105, 106 is the missing number, and then we go 107, 108, 109, 110. So, the missing number is 106, that's the number after 105 and before 107. Let's keep going. What is the missing number? Well, if I start at 100, the next number is going to be 101, and then we go to 102, 103, 104, we keep going. This is exciting. What whole number comes right before 105? Well, what whole number comes right before five? Well, four. So what number comes right before 105? Well, it's going to be 104. If you're going after 100 you get 100, 101, 102, 103, 104, and then you go to 105. All right, so they want us to figure out what the missing number is. And we see that they're counting, one, two three, all the way up to 10 and then here they're going from 11 to 20. They're counting all the way up to 120. But there's a missing square here. So, this is the number that is one larger than 118 and one less than 120. Well, if I was counting, I'd go 111, 112, 113, 114, 115, 116, 117, 118, 119, and then 120. Nineteen is before 20, so 119 is gonna be before 120. And 19 is after 18 so the number after 118 is going to be 119. Let's check our answer. Let's do one more of these. Well, we've done these a lot already. What number is missing? Right after seven comes eight, so right after 107 comes 108 and then 109 and 110.