⚡ Build the skills to land top-paying quant jobs. Offer ends in 26d 12h 21m 28s26 days 12 hours 21 minutes 28 seconds.
There are black(B) and red(R) cards in a standard deck. A run is number of blocks of consecutive cards of the same color. For example, a sequence RRRRBBBRBRB of only 11 cards has 6 runs; namely, RRRR, BBB, R, B, R, B. Find the expected number of runs in a shuffled deck of cards.