multiplication learning for 3 digits numbers for class 4 students
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Welcome to 3-digit multiplication! Before we multiply big numbers, let's remember place value. Every 3-digit number has hundreds, tens, and ones places. For example, 345 has 3 hundreds, 4 tens, and 5 ones. Understanding place value is the key to multiplying larger numbers successfully.
Now let's learn the partial products method. To multiply 234 times 3, we break 234 into its place values: 200 plus 30 plus 4. Then we multiply each part separately. 200 times 3 equals 600. 30 times 3 equals 90. 4 times 3 equals 12. Finally, we add all the partial products: 600 plus 90 plus 12 equals 702.
The standard algorithm is another way to multiply. Let's solve 456 times 7. We start from the ones place: 6 times 7 equals 42. We write 2 and carry 4. Next, the tens place: 5 times 7 plus 4 equals 39. We write 9 and carry 3. Finally, the hundreds place: 4 times 7 plus 3 equals 31. We write 31. Our answer is 3192.
Now let's multiply a 3-digit number by a 2-digit number: 123 times 24. First, we multiply 123 by 4, which gives us 492. Next, we multiply 123 by 20, which gives us 2460. Remember, 20 is 2 times 10, so we're really multiplying by 2 and adding a zero. Finally, we add our two partial products: 492 plus 2460 equals 2952.
Let's practice what we've learned! Here are some important tips: First, make sure you know your basic multiplication facts well. Second, always estimate your answer first to check if your result makes sense. For example, 567 times 8 should be close to 600 times 8, which equals 4800. The actual answer is 4536, which is indeed close to our estimate. Remember to practice regularly and break big problems into smaller, manageable parts. With practice, you'll become a multiplication expert!