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## Numbers & Operations - The Real & Complex Number Systems <159

### Unit 1: Lesson 1

Counting small numbers

# Counting with small numbers

Sal counts squirrels and horses.

## Want to join the conversation?

• why does 100 have 2 0
• It's because of place value. Zeros are place holders to make sure 1000 doesn't get confused with 100000000.
• Hey, fractions are 2/4 or 1/2 shayde.rakurku-hohepa.
• How to add quickly without thinking? Help.
• If you practice it a lot it will no longer feel like you are thinking about it
• Aren't counting numbers also known as whole numbers? Why are there two different names for the same thing?
• Like what Elizabeth Cummings said, counting numbers begin with the number one. This is the case because we cannot count with negative numbers. For example, I can't say that I have -2 apples.
Whole numbers are, by definition, numbers that don't have a fraction or decimal, because then, it wouldn't be whole. Whole numbers cannot be negative, and start with a zero.
• What is a quintillion?
• A quintillion is a number that is 1 followed by 18 zeroes(1,000,000,000,000,000,000.
• Why do we have a specific order of counting numbers,it could be just random also.
• If we didn't have a specific order of counting numbers, we would not be able to compare numbers. If we counted numbers in a random order, both 1 2 3 4 5 and 1 5 2 3 4 would be correct. In the first sequence, 2 is less than 5 because it comes first. In the second sequence, 5 is less than 2 because it comes first. How can 2 numbers be less than each other?
• so you just count and drag the pictures?
• yes,you just got to count how many pictures you have. hope you are having a great day today :)
• which is the biggest number ever !
• there is no biggest number but you can call the biggest number infinity
• I was just wondering how your able to rank up in the different courses. Like im on lvl 1. But i get all problems right but im still on lvl 1. How do i master each challenge
• If you mean the mastery challenges then listen to the others. If you mean the separate lessons then there's a Unit test which tests you on that Unit.
• What is infinite in real life. Like is there anything we can point to in reality that we know is truely infinite?
• In the world of surreal numbers and games, there are many varieties of infinity that are all meaningfully different from each other! Omega (which I'll call w) is what we usually think of as infinity. Varieties of infinity include but are not limited to w, w/2, squareroot(w), w - 1, w + 1, 2w, w^2, etc.

Have a blessed, wonderful day!

## Video transcript

- [Voiceover] Put seven squirrels in the box. All right, so that's one, two, three, four five, six, seven squirrels. I've put seven squirrels in the box. Let's keep going, this is lots of fun. Put four squirrels in the box. That's even easier than putting seven. One, two, three, four. I just click on the squirrel and then drag it into the box. All right, hopefully we see more animals. Oh, here we go, horses. Put nine horses in the box. One, two, three, four, five, six, seven, eight, nine horses. It's a lot of fun.