About this video
Sal counts dogs and mice arranged in circles and cookies that are jumbled up. He remembers which one he started with so he doesn't count anything twice, getting 8 dogs, 7 mice, 9 cookies and 19 mice.
You'll be able to
- count objects in a circle by remembering where I started.
- count each object only once.
- count mixed-up objects carefully.
Key words
- count once
- Giving each object only one number, never counting it again.
Transcript
- [Voiceover] How many dogs do you see? And I have the dogs down here, we just need to count them. So, if I'm starting with this dog, and I wanna make sure that I don't count him again, so I wanna remember, I'm starting with this top dog. One, two, three, four, five, six, seven, eight.
I see eight dogs. You might be tempted to go, nine. But I already counted this dog. So there's only eight dogs. So I see eight dogs. So let's check our answer. Got it right. How many mice do you see? Same thing, I like to start with the top mouse, but we have to remember, if I'm gonna start counting with the top mouse, I don't wanna keep counting the top mouse.
So one, two, three, four, five, six, seven. Now, you might be tempted to go eight, but we already counted this top mouse. So there's only seven mice here. Seven mice. You gotta be careful not to keep going in circles and counting the mice over and over and over again.
You only wanna count each of the mice once. Let's do another one. This is too much fun. How many cookies do you see? All right, they're all jumbled up here, and we just have to be careful not to count the cookie twice. So let's see, one, two, three, four, five, six, seven, eight, nine.
There are nine cookies. I see nine cookies. How many mice are there? Okay, now, here there are a lot of mice. So there's one, two, three, four, five, six, seven, eight, nine, 10, 11, 12, 13, 14, 15, 16, 17, 18 19 mice. There are 19 mice there. That's a lot of mice.
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