I'm very new to probability and my professor hasn't gone into detail with it but we must know it for the class. I'd appreciate help with these questions.
Suppose a slot machine has $3$ reels with $7$ different symbols on each, jackpot is when all $3$ reels have the same symbol. All three reels are selected independently. What is the probability of getting jackpot on the first try?
My answer $(1/7)^3 = 0.29\%$
$X$ represents the number of independent and successive lever pulls to get a jackpot. How many bits of info are conveyed by making a jackpot after $X$ tries?
What is the entropy?
I'm pretty clueless on the last two, I'd greatly appreciate any help. Thank you.