Philosophy Logic Question?

[miguel g]

Heya guys. Logic is my favorite branch of Philosophy so far, and I'm having great fun with it, but I'm stuck on a little problem, and I was wondering if you guys could give me a helping hand. The thing is, that we've just started studying the last three basic rules of logic, which are the deduction theorem, the reduction to absurd and the third one which we are yet to see. Anyways, I can't seem to figure out this exercise, I've done a truth table to see if it's a tautology, and it is, but I can arrive at the same conclusion using the step by step analysis. So, if you guys could at the very least give me some points, It would be VERY much appreciated!

1. P--> (Q --> R)

And you have to reach the conclusion: Q --> (P --> R)

Again, thanks for the help! Oh and btw you can use all the basic logical laws EXCEPT the third one which uses suppositions, which we haven't seen yet. Good luck .