Answer :

1/6 + 2/3=
1/6+4/6 being 6 the common denominator
5/6 which is in simplest form
Cantona1z
1/6+2/3=5/6 ( Decimal:0.83333)
Steps 
1/6+2/3
Combine the fraction using the LCD: 1+2*2/6
1/6+2/3
Find the LCD for 1/6+2/3:6 
Factor each  denominator into its primes
6=2*3 
Adjust Fractions based on LCD
1/6+2*2/6
Since the denominators are equal, combine the fractions: a/c+b/c=a+b/c 
=1+2*2/6
Refine 
5/6