Step-by-step explanation:  
Step 1: See Steps Below 
5 1/3 + 7 1/4 
= 16/3 + 7 1/4
= 16/3 + 29/4
= 151/12
= 12 7/12
 
Explanation in words:  
- The first step is to add whole numbers which are 5 + 7: 12 
- The second step is to combine the fractions 1/3 + 1/4: 7/12 
- The third step is to solve the fraction. So it will result as 12 + 7/12 
- The answer is 12 7/12 
Easy Steps: See Attachment 
 
Answer:  
12 7/12 
(Decimal: 12.583333) 
 
Hope this helps.