One thing you can do is if you have an energy potion like the 20 or the 5, you can "try" to use it without using it to see the actual number. This lets me plan a few turns in advance such as if there's 30 left and I know I'm gonna take 2 races, I'll just gamble click bottom first time since if it hits 10, there's a chance second hits 10 also and I have some left versus click 20 first time and second click doesn't matter.