Got math? Mystery Cache

My first ever mystery Should be an easy one for most.  In middle school I failed math really bad.  Still today as a big kid I still had to ask my middle school math teacher about this.  I gave her the answer and she sent me these three questions. This is a lock box locked to a steel fence. You need this combo to open it and log the cache You need to only answer any one to get the combination. Put in the log which one you answered to get credit for the cache. If you need help message me. Also look at the hint!  Happy caching

1) 50+20 (40+15) -1 * 100 - 29= ?

2) 500+1000 / 2 + 7 * 3 = ?

3) 3x -1000 = 2063 Find x

You can validate your puzzle solution with certitude.