general help for new user

Help! Why are my tracks different sizes? I have imported an mp3 into audacity and cut out bits that I didn’t want. I then imported the same track into audacity again, however the two identical tracks are different sizes (if that makes sense) When played together, even when lined up, one is way ahead of the other?

I am using the latest version of audacity on a mac OS X 10.9.3

They are different shows. They started out the same clip but they’re not any more.

Import the sound clip and cut it so as to reduce the length of the show.
Import the exact same clip and it’s pure and clean with no editing or cutting. The first show is going to be shorter.

You can use the MUTE and SOLO buttons on the left to listen to one without the other or de-select both to listen to both at the same time.

What is the goal? Why did you import one sound clip twice? I might do that to cut a work for two different clients and I wanted to check the rhythm of the shows.