Adding and Subtracting Decimals with Positive and Negative Numbers

-40 + 15.05

• 55.05

• 24.95

• -24.95

• 14.65

When adding decimals 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 decimals with different signs you....

• subtract and take the sign of the larger number

• add the opposite

• add and keep the sign

• subtract and keep the sign

-7.79 + 5.4

• 4.61

• -2.19

• -2.39

• 2.11

-1.3 + 3.6 = ?

• 2.3

• -2.3

• 4.9

• -4.9

-51 + 81.623

• 30.623

• -30.623

• 132.623

• -132.623

-4.2 + 0.7

• -10.1

• -3.5

• -1.7

• -5.1

-2.5 + (-2.5)

• -5

• 0

• 5

-7.9 - 4.25

• 3.65

• -3.65

• -12.15

• -5.94

-2.5 + 1.3

• 6.3

• -1.2

• 6.79

• -5.1