2 1/2 / 3/4 can be seen as 5/2 / 3/4
. When we divide two fractions we get the reciprocal of one of them and multiply the other with it.
In this case: 3/4's reciprocal is 4/3. So, 5/2 / 3/4 is 5/2 * 4/3. This is 20/6, which can be simplified to 10/3, or 3 and 1/3.