2/3 = 4/6
------So, no.
5/6 and 7/8
------common denominator is 24. Need form of one to convert fractions.
4*5/4*6 = 20/24
3*7/3*8 = 21/4
-------So 7/8 is larger than 5/6. ( try the last one )
5/6 and 4/5
------common denominator is 30
5*5/5*6 = 25/30
6*4/6*5 = 24/30
------So, no.
The only fraction here larger than 5/6 is 7/8.