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### Course: Early math review > Unit 1

Lesson 2: Numbers 0 to 120# Counting by tens

Practice counting by tens using numbers and ten frames.

## Want to join the conversation?

- So counting by ten is like counting regular numbers with a zero at the end?(29 votes)
- Not always, you can count by ten starting from any number. For example, if I want to start from 6 and count by ten, it would go like this:
*6, 16, 26, 36, 46, 56, 66, 76, 86, 96, 106,..., etc.*(16 votes)

- At0:16, how does 30 come after 20? Doesn't adding 1 to a number increase the number in the left and the right, so the number after 20 would be 31?(4 votes)
- You're not adding 1, you're adding 1 ten (So, ten). 31 would be the answer if you were adding eleven, which is 1 ten and 1 one. In any case, adding a 1 to a number doesn't increase both numbers.(10 votes)

## Video transcript

- [Tutor] So we are
told let's count by tens and we go 10, 20, blank, 40, 50, 60, 70, 80, 90, 100, what number did we miss? Pause the video, what number
did we miss right over here? Well, if we're counting by tens, we would go 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, so we're missing 30, so which choice right over here has 30? Well, if we scroll down a
little bit, we see right there, that is our choice. Let's do another example. So here we are asked which ten frames show 20? A ten frame is just a fancy word for one of these blocks or these frames, that have 10 objects in them, you can see it right over here,
one, two, three, four, five, six, seven, eight, nine, 10, so which of these ten frames show 20? Well, 20 is two groups of 10, so this is 10 and then 20, so
that's 20 right over there, choice B is 10, 20, 30, 40, choice C is 10, 20, 30, so we can feel good about choice A. Here we're told drag the ten
frames into the box to make 40. So let's see, here this
is 10, right over there, then we get another 10, gets us to 20, then another 10 gets us to 30 and then finally another 10 gets us to 40, 10, 20, 30, 40, we're done.