Adding and Subtracting Rational Numbers

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

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

What is the value of 18 - 23.2 ?

• -5.2
• -5.8 
• 5.2
• 5.8

4/9 + (-2/3) = 

• 1 1/9
• -1 1/9
• 2/9
• -2/9

1/4 - (3/10) = 

• 1/20
• -1/20
• 11/20
• -11/20

-1 ⁷/₈ + (-3 ¹/₂)

• 5 ³/₈
• -5 ³/₈
• 1 ⁵/₈
• -1 ⁵/₈

2 ⁶/₉ + (- 5 ¹/₄)

• 7 ¹¹/₁₂
• -7 ¹¹/₁₂
• 2 ⁷/₁₂
• -2 ⁷/₁₂