So, what I like to do when I come across this problem is divide the fractions...
1/2= 0.5
5/6= 0.83
2/7= 0.28
4/2= 2
Then, you put them in order. The greatest will be which ever is a whole number or a decimal closest to one.
Here is the order...
5/6, 2/7, 1/2, 4/2
HOPED THIS HELPED!