# Math

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There are 7 rap songs, 7 rock songs and 5 classical songs to select from. Three songs are to be chosento play at random
-what is the probability that only classical songs are selected?
-what is the expected number of classical songs to be selected?

• Math -

number of all possible triples selected = C(19,3) = 969

number with exactly one classical, 2 from the others
= C(5,1)xC(14,2) = 5(91) = 455

prob of your event = 455/969

• Math -

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