[Request] If all 3 of these have the same % then what one would you buy to get the most of one particular prize?

I'm not sure this is the best place to post this. Please remove if it doesn't fit this sub.

Crystal 1- 2k cost.

Crystal 2- 20k cost.

Crystal 3- 50k cost.

Odds 1- 0.02%, 2- 0.35, 3- 0.65%, 4- 15%, 5- 83.98%.

If I have 500k chips and I want to get the most of prize 4 as I can then which would be the best to buy? The 20k gives me 10x the amount of prize 4 as then 2k one does, so I know I'd have to hit the 20k one once compared to the 2k one 10x to get the same amount of prize 4. The 2k one gives me more chances at hitting prize 4 but less opportunities. Could someone explain which would be the best one to buy and why? Does it change if I only have 250k chips? What if I had 1M chips does it change?

Im assuming most people would say it's just a game but it's teaching me how probability works, my brain is telling me that the chances of hitting the 20k one is better if I had say 20k chips because it's unlikely id hit prize 4 10x compared to once and I'd need to hit it 10x to get the same amount of prize 4.

Hope I explained that well enough, and also thanks in advance if anyone does take the time to explain this to me. I've already asked if I had more or less chips would that then change the crystal id want to pick but I'm going to word it differently and ask if there's certain benchmarks, like 100k 1m 10m? Hope that makes sense.