Using Friendly Numbers in Addition

The video tutorial explains the concept of compensation in two-digit addition. Compensation is a technique used to simplify addition by adjusting numbers to create 'friendly' numbers, such as multiples of ten. The video provides three examples: 27 plus 15, 26 plus 18, and 37 plus 16, demonstrating how to adjust the numbers to make the addition easier while maintaining the same sum.

What is the main purpose of using compensation in addition?

• To change the sum of the numbers

• To make the problem easier to solve

• To make the numbers smaller

• To make the numbers larger

In the example of 27 plus 15, what is the friendly number that 27 is adjusted to?

• 40

• 30

• 35

• 25

How does compensation affect the overall sum of the numbers?

• It doubles the sum

• It does not change the sum

• It decreases the sum

• It increases the sum

In the example of 27 plus 15, what does 15 become after compensation?

• 16

• 10

• 12

• 14

What is the result of 30 plus 12 in the example of 27 plus 15?

• 46

• 44

• 42

• 40

In the example of 26 plus 18, what is the friendly number that 18 is adjusted to?

• 20

• 22

• 18

• 15

What does 26 become after compensation in the example of 26 plus 18?

• 22

• 24

• 26

• 28

What is the result of 24 plus 20 in the example of 26 plus 18?

• 42

• 44

• 46

• 48

In the example of 37 plus 16, what is the friendly number that 37 is adjusted to?

• 35

• 38

• 40

• 42

What does 16 become after compensation in the example of 37 plus 16?

• 15

• 10

• 12

• 13