# rcourtie/khan-exercises forked from Khan/khan-exercises

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 Dependent probability

You have NUM_COINS coins in a bag. NUM_UNFAIR_COINS of them are unfair in that they have a PERCENT_CHANCE_UNFAIR_HEADS\% chance of coming up heads when flipped (the rest are fair coins). You randomly choose one coin from the bag and flip it NUM_FLIPS times.

What is the probability, written as a percentage, of getting NUM_FLIPS heads? Round your answer to the nearest hundredth of a percent.

You can only pick a fair coin or pick an unfair coin. There is no other outcome.

What chance do you have of picking an unfair coin? How about a fair coin?

An unfair coin occurs UNFAIR_COIN_FRACTION_STRING of the time.

A fair coin occurs the rest of the time, or FAIR_COIN_FRACTION_STRING of the time.

For that UNFAIR_COIN_FRACTION_STRING of the time that you pick an unfair coin, what is the chance of flipping NUM_FLIPS heads using that unfair coin?