How is that you got 1 in 7733 with 100TH/s ?
It's rather simple, take total network hashrate (can be found using a simple google search, it's not 100% accurate and you can use diff to derive it but not that it matters given the scope) you divide it by your "potential" hash rate , you get a number X, that number is your "share" of the network, it simply means how many blocks on average you would wait to hit a block
So current bitcoin hashrate is around 130EH or 130,000,000 TH, with 100TH your chances are 1 in 1,300,000 for every block, since there is on average 144 blocks a day, you can divide that by 144 and you get 1 in 9,027 for TH. The difficulty / total hashrate was lower when the member above did that math, just goes out to show how a few days can make a lot of difference.
Now that you know you only have 1 in 9k chances mining with 100TH, you can apply the same math on your GPU, how fast does it hash, maybe 50MH? that is 0.00005TH, your chances per day will increase from 9027 to 18,055,555,555, that's nearly about 20,000,0000% less luck, mind you, 1 in 9027 is already as bad as it gets.
