one way to compare two ratios is the make the denominator the same, then compare the numerator.
for example, 3/4 and 5/6, the least common multiple of 4 and 6 is 12, so make the denominator into 12
3/4=9/12, 5/6=10/12, 10 is larger than 9, so 5/6 is larger than 3/4
another way to compare is to "cross times"
for example, again 3/4 and 5/6, multiple 3 and 6, you get 18, multiple 4 and 5 you get 20, 20 is larger than 18, so 5/6 is larger than 3/4