No. We have 3 angles of triangle ABC congruent to 3 corresponding angles of triangle LMN. That is AAA. To use ASA, you need two angles and an included side. With three angles, you can prove the triangles similar, but not congruent.
The reason you can only compare the numerators is because the denominators are the same- leaving little comparison to really make. The numerators will determine which fraction is greater or smaller.
Ex. 4/5 or 3/5
which is greater? Which is smaller?
It can be seen that the denominators are the same, now finally comparing the numerators will answer both questions.