Adding and Subtracting Decimals with Positive and Negative Numbers

4.5 - 18.6

• -14.1

• 14.1

• 23.1

• -23.1

Rewrite the problem as addition.

-5.66 - (-4.1)

• 5.66 + (-4.1)

• -5.66 + 4.1

• -5.66 + (-4.1)

• -5.66 - 4.1

-23.4 - 3.4= 

• -20

• 26.8

• -26.8

• 20

-40 + 15.05= 

• 55.05

• 24.95

• -24.95

• 14.65

5.23 - (-9.1)

• -3.87

• 3.87

• 4.32

• 14.33

-7 - (-8)

• 1

• -1

• 56

• -56

When adding with the same sign you.....

• subtract and take the sign of the larger number

• add the opposite

• add and keep the sign

• subtract and keep the sign

When adding with different signs you....

• subtract and take the sign of the one you have more of

• add the opposite

• add and keep the sign

• subtract and keep the sign

What is the value of 18 - 23.2 ?

• -5.2

• -5.8 

• 5.2

• 5.8

-9 + (-5)

• -14

• 14

• -4