Solution:
Convert all the numbers to decimal form;
1/3 = 0.3 (where 3 is recurring)
33/100 = 0.33
5/6 = 0.83 (where 3 is recurring)
2/3 = 0.6 (where 6 is recurring)
The correct choice is 1/3 since its the only choice that don't give a limitation on rounding up the decimal value to 1 decimal place.