Easiest way to compare 2 fractions is to give them a common denominator.
The quickest way to do that is to multiply top and bottom of the one fraction with the bottom of the other, and vice versa.
So for 7/4 and 1/6, you multiply top and bottom of 7/4 by 6, and top and bottom of 1/6 by 4.
This gives you 42 / 24 compared with 4/24 and the ordering of these is obvious.
It occurs to me there's a quick way of doing it by eye in this case:
7/4 is between 1 and 2, 7/2 is between 3 and 4 and 1/6 is between 0 and 1.