When dividing fractions you must remember the KEEP, CHANGE, FLIP rule.
KEEP - The first fraction you KEEP as it is, you don't change it.
CHANGE - You now change the sign from a division to a multiplication.
FLIP - You FLIP the last fraction over so the denominator is now the numerator and vice versa.
You now have a simple multiplication question which you should be familiar with. If not then you simply multiply the two numerators to get the answer numerator, and multiply the two denominators to get the answer denominator.