Understanding Big Multiplication
Multiplying larger numbers might seem tricky, but it's just like regular
multiplication with a few extra steps!
When we multiply a 2-digit number by a 3-digit number, we break it down into smaller, easier problems.
We'll use the distributive property to multiply each digit separately and then add all the partial
products together. It's like building a multiplication sandwich!
Step-by-Step Method
Let's Practice Together!
Example 1: 45 × 123
Click to see the step-by-step solution!
Let's solve 45 × 123:
1. First multiply 45 × 3 = 135
2. Next multiply 45 × 20 = 900 (write 45 × 2 and add a zero)
3. Then multiply 45 × 100 = 4500 (write 45 × 1 and add two zeros)
4. Now add them together: 135 + 900 + 4500 = 5,535
Answer: 45 × 123 = 5,535
Example 2: 78 × 345
Try solving this one first, then check your answer!
Let's solve 78 × 345:
1. First multiply 78 × 5 = 390
2. Next multiply 78 × 40 = 3,120 (write 78 × 4 and add a zero)
3. Then multiply 78 × 300 = 23,400 (write 78 × 3 and add two zeros)
4. Now add them together: 390 + 3,120 + 23,400 = 26,910
Answer: 78 × 345 = 26,910
Parent Tips 🌟
- Real-world practice: Have your child calculate totals when shopping (e.g., price per item × quantity) to make math meaningful.
- Break it down: Encourage your child to solve problems on graph paper to keep numbers neatly aligned.
- Make it fun: Create a multiplication bingo game with 2-digit × 3-digit problems as a fun way to practice.