Exam Maths Puzzle Numerical Ability

there are 5 physics books, 4 maths books and 3 chemistry books are on the table. What is the probability to took at least one book.

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the ways of selecting none book 12c0=1
probability to took at least one book=1-1/12=11/12
8 years agoHelpfull: Yes(1) No(0)

Exam Other Question

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