$60 should be the minimum

Easy. 12 times a number needs to be a multiple of 5 in order to spend the remainder on 5 dollar tickets. 12*5=60 is the lowest possible amount. Of course Ian raises a good point that 0 should have been an option. That would have tricked quite a few people and would have been very GMATish.

I did the same u guys did, but the OA is 120. I have been studying for two months and I have my exam on Monday. I solved 800 score's and MGMT's full tests, but I wish I did no go through unsafe sites from which I bought the test containing the previous question.

Hi Finance, happy to see your progress. I wish you all the luck for your exam.

Since you raised a point of unsafe sites. I would like to take this opportunity to tell everyone, including people who are following me, to be very careful in dealing with these third party vendors. Remember this is not an official Gmat material. Further, Hacks claim that this material was hacked from the GMAT database some time back. Just to update you on this - GMAT clearly claims that they have already deleted material that was compromised. Further, after the claim and law suit on the HACKS, Gmat also clearly stated that anyone found using these websites or their material will be banned permanent from giving GMAT. Till August 2010, if you would open gmathacks website you would be directed to an official site that would caution you to not use such material. I think now it has been settled (since i don't get redirected anymore)
Still the authenticity of the material is doubtful. As Eric mentioned in one of his posts that we are still sure how the material is because our students hardly use it.
To conclude i would advice people to stick to authentic and reliable source for questions since these questions are constantly reviewed by experts. Remember correct question leads to a better understanding.

All the best