Addition and Subtraction Relation

Ball: 13c

Marcus has 20c.

How much change does he need?

• 20c - 13c = 7c

• 13c - 20c = 7c

• 20c + 13c = 33c

• 13c + 20c = 33c

Box of chocolate: 21c

Faith has 30c.

How much change does he need?

• 30c + 21c = 51c

• 21c - 30c = 9c

• 30c - 21c = 9c

• 21c + 30c = 51c

What is the method to 'undo' an operation called?

• updo

• addition

• subtraction

• inverse

Why do we use the inverse?

• To waste time

• To check our answer

• Because the teacher told us so

• Because we are working with money

Alice goes to buy a pair of shoes. After she buys the shoes she will have:

• less money in her purse

• more money in her purse

When we are doing addition

• the number gets smaller

• the number gets bigger

Choose the correct calculations using these numbers: 8, 12, 4

• 8 + 4 = 12 and 12 - 8 = 4

• 8 - 4 = 12 and 12 + 8 = 4

The inverse of an addition question like this

12 + 3 = 15,

is:

• multiplication

• addition

• division

• subtraction

The inverse of a subtraction question like this

12 - 3 = 9,

is:

• multiplication

• addition

• division

• subtraction

16 + 4 = ____ and ____ - 4 = 16

• 10

• 20

• 16

• 4