ClassX Video Lessons Youtube Channel Virtual Elementary School Grade 2 Math: Subtraction Rocks with Base Ten Blocks
Hey there! Do you know what 3 minus 1 is? Yes, it’s 2! But what if we have bigger numbers to subtract? Let’s learn how to do that together!
First, we need to write the numbers one below the other. The tens go on the left, and the ones go on the right. We can use something called base ten blocks to help us. Imagine we have 4 rods and 5 little blocks. This makes the number 45.
Now, we want to take away 17 from 45. Let’s start with the ones. We need to take 7 away from 5. Uh-oh, we only have 5 blocks, so we can’t take 7 away. What should we do?
We can regroup! This means we take one rod (which is 10 blocks) and break it into 10 little blocks. Now, instead of 5 blocks, we have 15 blocks in the ones place. Yay! Now we can take 7 away from 15, which leaves us with 8. We write 8 in the ones place of our answer.
Next, we subtract the tens. Since we moved one rod to the ones place, we have 3 rods left. Now we subtract: 3 minus 1 equals 2. We write 2 in the tens place of our answer.
So, we have 2 rods and 8 little blocks, which makes the number 28. That means 45 minus 17 equals 28. Great job! You just solved a subtraction problem!
Keep practicing, and subtraction will become super easy and fun!
Build Your Own Base Ten Blocks: Gather some small objects like buttons, coins, or small blocks to represent the ones, and use sticks or straws to represent the tens. Try to solve the subtraction problem 63 minus 29 using your homemade base ten blocks. Can you regroup and find the answer? Share your solution with a friend or family member!
Subtraction Scavenger Hunt: Go on a scavenger hunt around your home or classroom to find items that you can use to practice subtraction. For example, if you have 10 apples and you eat 3, how many are left? Write down your subtraction problems and solve them using the objects you find. How many different subtraction problems can you create?
Story Time Subtraction: Create a short story where a character needs to solve a subtraction problem using base ten blocks. For example, “Lucy had 50 candies, and she gave 23 to her friends. How many candies does she have left?” Draw pictures to illustrate your story and show how the character uses regrouping to find the answer. Share your story with the class!
Sure! Here’s a sanitized version of the transcript:
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Do you know what 3 minus 1 is? That’s right, the answer is 2. Have you ever wondered how to solve subtraction equations with larger numbers? Let’s find out!
Let’s solve the equation 45 minus 17. To start, let’s line up the equation vertically so that the tens are on the left and the ones are on the right. We can use base 10 blocks to help us solve this equation. We have 4 rods and 5 units, which represents 45. We need to take 17 away from 45.
Let’s start by subtracting the ones. We need to take 7 away from 5. Since we only have 5 blocks, we can’t take 7 away. This means we will have to regroup to make a larger number in the ones place. To do this, we can take one of the rods and break it into 10 units. Now we have 15 units in the ones place. We change the 5 to 15, and now we can take 7 away from 15, which leaves us with 8. We write the number 8 in the ones place of the answer.
Now we can subtract the numbers in the tens place. Since we moved a rod over to the ones place, we only have 3 rods left. Now we can subtract the tens: 3 minus 1 equals 2. We write the number 2 in the tens place of the answer.
We have 2 rods and 8 units, which makes the number 28. Therefore, 45 minus 17 equals 28. You took action to solve a subtraction equation!
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