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2nd grade
Course: 2nd grade > Unit 2
Lesson 1: Intro to place value- Intro to place value: FAQ
- Intro to place value
- Use place value blocks to show numbers within 1,000
- Place value blocks within 1,000
- Place value tables within 1,000
- Place value tables within 1,000
- Identifying value in digits
- Identify the value of a digit (ones, tens, hundreds)
- Creating the largest number
- Create the largest number
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Intro to place value: FAQ
Frequently asked questions about the introduction to place value.
Why do we need to learn about place value?
Place value is a key concept in understanding how numbers work. Without it, we wouldn't be able to tell the difference between, 100 and 10. We also use place value when we're adding, subtracting, multiplying, and dividing numbers, so it's important for all kinds of math!
Understanding place value is important in all kinds of math, from counting money to telling time to measuring things. Being able to compare numbers is also essential in many situations, like when we're trying to figure out which team won a game or who has the highest score.
What's the difference between standard, word, and expanded form?
Standard form is just the way we usually write numbers, like 567. Word form spells out the number in words, like "five hundred sixty-seven". Expanded form breaks the number down into its component parts, like 500, plus, 60, plus, 7.
What does "regrouping" mean?
Regrouping is when we exchange ten of one kind of unit for one of the next unit. For example, we can regroup ten ones into one ten, or ten tens into one hundred.
For example, we can regroup start color #7854ab, 50, end color #7854ab, start text, space, t, e, n, s, end text into start color #7854ab, 5, end color #7854ab, start text, space, h, u, n, d, r, e, d, s, end text.
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What are even and odd numbers?
An start color #0c7f99, start text, e, v, e, n, end text, end color #0c7f99 number is a number that can be split into 2 equal groups.
We find start color #0c7f99, start text, e, v, e, n, end text, end color #0c7f99 numbers by making sure every object in the group has a pair.
Examples of start color #0c7f99, start text, e, v, e, n, end text, end color #0c7f99 numbers are start color #0c7f99, 2, end color #0c7f99, comma, start color #0c7f99, 4, end color #0c7f99, comma, start color #0c7f99, 6, end color #0c7f99, comma, start color #0c7f99, 8, end color #0c7f99, comma, start color #0c7f99, 10, end color #0c7f99, comma, point, point, point
An start color #9e034e, start text, o, d, d, end text, end color #9e034e number cannot be split into 2 equal groups.
We find start color #9e034e, start text, o, d, d, end text, end color #9e034e numbers by trying to pair objects and finding there is not always a pair.
Examples of start color #9e034e, start text, o, d, d, end text, end color #9e034e numbers are start color #9e034e, 1, end color #9e034e, comma, start color #9e034e, 3, end color #9e034e, comma, start color #9e034e, 5, end color #9e034e, comma, start color #9e034e, 7, end color #9e034e, comma, start color #9e034e, 9, end color #9e034e, comma, point, point, point
How do we compare two numbers?
We usually start by looking at the leftmost digit. If one number has a larger digit there, it's bigger. If the digits are the same, we move on to the next digit and compare those. If the numbers are the same all the way through, they're equal!
Want to join the conversation?
- FAQ means "frequently asked questions".(3 votes)
- why are odd numbers odd and why are even numbers even?(4 votes)
- From Khanmigo:
Great question! 🎉 Even and odd numbers are like two sides of a coin, each unique in their own way.
An even number is like a pair of shoes, you can always divide it into two equal groups without any leftover. For example, if you have 4 apples, you can give 2 apples to your friend and keep 2 for yourself. No apple is left alone. 🍎🍎 | 🍎🍎
On the other hand, an odd number is like a pair of socks with one extra. You can try to divide it into two equal groups, but there will always be one left over. For example, if you have 5 oranges, you can give 2 oranges to your friend and keep 2 for yourself, but there will be one orange left over. 🍊🍊 | 🍊🍊 + 🍊
If you'd like to dive deeper into this topic, I recommend checking out our video "Intro to even and odd numbers" at https://www.khanacademy.org/math/cc-third-grade-math/arithmetic-patterns-and-problem-solving/imp-patterns-in-arithmetic/v/introduction-to-even-and-odd(1 vote)
- does dividing have something to do with place value?(0 votes)
- Yes. Solving addition, subtraction, multiplication, and division problems using numbers with more than one digit will sometimes need regrouping. An understanding of place value is needed to understand regrouping.
Have a blessed, wonderful day!(1 vote)