To put a whole number and a fraction together you must convert the whole number into fractional form first.
Since 2 is the whole number, and one sixth is the fraction, we must change to 2 into sixths. To do this we multiply 2 by the fraction 6/6.
2 x 6/6 = 12/6
Now both numbers have 6 in the denominator, and we can add the tops.
12/6 + 1/6 = 13/6
Any whole number in fractional notation is itself over 1. so, 2 in fractional notation is 2/1. Simple!
Fractional notation for 6.5 is 13/2
2 - 1
121/2
125/2
61/2 or 13/2
2 1/2
5/2
5 2/5
2.5 = 21/2
4 1/2
2 59/125