1. How do you multiply 512 x 46? Those are really big numbers!

2. In this lesson you will learn how to multiply multi-digit numbers by using the standard algorithm.

3. Let’s Review Product – The result when two numbers are multiplied. For Example: 4 x 5 = 20 product

4. Multiplication is repeated addition. 32 + 32 + 32 + 32 + 32 32 x 5 Multiplication is faster!

5. Multiplying by powers of 10. 36 x 10 = 360 36 x 100 = 3,600 36 x 1,000 = 36,000

6. A Common Mistake Multiplying each digit as if it represents a number of “ones.” It is important to remember the place value of each digit. 36 x 5 = 30 x 5 + 6 x 5

7. Let’s Review Core Lesson Multiply 512 x 46 512 x 46 First, we need to multiply 512 by 6. Then we need to multiply 512 by 40.

8. Let’s Review Core Lesson 512 x 46 2 1 730 0 Adding a zero shows that we are multiplying by 10’s. 8 4 20 + 23,552 Next, we add the partial products.

9. Let’s Review Core Lesson 405 x 57 5 3 328 0 Adding a zero shows that we are multiplying by 10’s. 5 2 20 + 23,085 Next, we add the partial products. 2

10. In this lesson you have learned how to multiply multi-digit numbers by using the standard algorithm.

11. Let’s Review Guided Practice Multiply 422 x 18.

12. Let’s Review Extension Activities Write a real world problem that could be solved by using 32 x 12.

13. Let’s Review Extension Activities Every student received 24 pencils. If there are 20 students in my class, how many pencils did we have in all?

14. Let’s Review Extension Activities Write a multiplication equation that has a product of 3,600.

15. Let’s Review Quick Quiz Multiply 290 x 73.

16. Let’s Review Quick Quiz Multiply 64 x 48.