Standard algorithm multiplication

multiplication

1. When should we multiply? When we need to add the same number many times, we need to multiply

2. Standard Algorithm (long) multiplication method

3. Multiply by 2 digit number Ex: 5 3 4 X 4 6 Step 1 Write the problem – lining up the place values ( ones under ones) and tens under tens X 5 3 4 4 6

4. X 5 3 4 4 6 Step 2 Multiply the bottom number in the ones palce by the top number in the ones place , tens place and hundreds place. 4 X 6 = 4 2 3 X 6 = 18 +2 = 2 5 X 6 = 30 +2 = 3 2

5. X 5 3 4 4 6 Step 3 As we are going to multiply by tens place number 0 should be added in ones place of answer 3 2 0 4 2 2

6. X 5 3 4 4 6 Step 4 Multiply the bottom number in the tens place by the top number in the ones place , tens place and hundreds place. 3 2 0 4 2 2 3 X 4 = 12 +1 = 1 3 4 X 4 = 6 1 5 X 4= 20+1 = 2 1

7. X 5 3 4 4 6 Step 4 Add the numbers in answer part 3 2 0 4 2 1 3 6 0 2 2 1 1 + 4 6 5 4 2

8. 5 3 4 X 4 6 = 24564

9. 2 1 7 X 5 3 Answer 1 1,5 0 1