In a random drawing with 50 entries are the odds of winning better if I:
A. Enter 1 contest 3 times
or
B. Enter 3 contests 1 time
In a random drawing with 50 entries are the odds of winning better if I:
A. Enter 1 contest 3 times
or
B. Enter 3 contests 1 time
In the first case, you have three entries out of 50, so your chance of winning assuming all drawings have equal chance of being picked is $\frac{3}{50}=0.06.$
If you enter 3 contests 1 time, and I assume each contest is the same, then your chance of winning at least one of them is the complement to losing all of them. This probability is given by $ 1-\left(\frac{49}{50}\right)^3=\frac{7351}{125000}\approx 0.058808. $ So it seems you have a slightly better chance of winning at least once if put all three of your bets in one contest.