There are only FIVE final outcomes for this system
50% of the time a victim tries this system, he will lose $10.
25% of the time a victim tries this system, he will lose $20.
12.5% of the time a victim tries this system, he will WIN $20 (even money)
6.25% of the time, the victim will break even
6.25% of the time, the victim will win $120!

This means that on 76.25% attempts, the victim will break even or LOSE money.
They will make even money only 12.5% of the time.
They will ‘hit the jackpot” only 6.25%.

Over a long period of time, the odds are exactly even!