Let make the fractions to decimal. To make the fraction to decimal you have to divide the numerator by the denominator. The numerator is the top part of the fraction and the denominator is the bottom part of the fraction.
Calculations
2/3 2 ÷ 3 = 0.666.....
5/6 5 ÷ 6 = 0.833...
0.833.. is greater then 0.666... Therefore 5/6 is greater