Skill 18B
Related Addition and Subtraction

Which subtraction sentence below is a related fact to 5 + 8 = 13 ?
Explain why.

 

5 + 8 = 13

 
a. 8 - 5 = 3
 
b. 13 - 8 = 5
 
c. 13 - 13 = 0
 
d. not sure