Let's make them both improper.
14*5+11=81, so 81/14 is the improper fraction of 5 11/14
Change the denominators to 56.
81*4=324, so 324/56 is the first fraction.
31*7=217, so 217/56 is the second fraction.
324+217= 541
----- ----- -----
56 56 56
541/56 = 9.66
\(9{66\over100}\)
Simplify
\(9{33\over50}\)
So, \(5{11\over14}+{31\over8}=9{33\over50}\)
.