SaiBook.us Multiplication

Lesson Example Discussion Quiz: Class Homework

Example

Title: Multiplications

Grade: 4-a Lesson: S1-L7

Explanation: The best way to understand multiplications is by looking at some examples. Take turns and read each example for easy understanding.

Examples:

Step: 1a

Find the product of 45 x 17

Place the multiplicand 45 on top, and the multiplier is 17.
Multiply the ones digit of the multiplier 7 with the multiplicand 45.
This will give 45 × 7 = 315. This is the first partial product that will be placed in one line."

$1a$

Explanation: In this step, multiply 45 by 7. Multiply 5 by 7 to get 35. Place 5 in the one’s place, and carry 3 to the tens column. Multiply 4 by 7 to get 28. Add a carry-over of 3, and we go for it 28 + 3 =31 to get 31. We get the answer is 315. This is the first partial product placed in one line.

Step: 1b

Multiplying with the tens column.This will give 45 × 1=45. Write a 0 in the one’s column as shown below.
Multiply the one’s digit on the top number with the ten’s digit of the bottom number, i.e., 5 × 1 = 5
Multiply the tens digit on the top number and the tens digit of the bottom number, i.e., 4 × 1 = 4. The value of a second partial product is 450.

$1b$

Explanation: In this step, multiply the bottom tens digit, which is 1, by the number on the top which is 5. So, 5 x 1 = 5. Write down the number 5 next to the 0. For 4 x 1 = 4, write down the number 4 next to the 5 that you already wrote down. This way, you will get the final answer of 450. This is the second partial product placed in another line.

Step: 1c

Add both partial products to get the final product
This will be 315 + 450 =765.

$1c$

Explanation: Add both of your results to get a final answer. Now need to add 315 + 450 to get 765.