A woman who goes to work long before sunrise every morning gets dressed in the dark. In her socks dr

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22 Mar 2019 Probability

A woman who goes to work long before sunrise every morning gets dressed in the dark. In her socks drawer she has 9 black and 12 blue socks. What is the probability that her first pick was a black sock, but her second pick was a blue socks?

OPtion

1) 17/70
2) 8/35
3) 9/35
4) 19/70
5) 23/70
6) 7/36
7) 9/37
8) 6/35
9) 11/45
10) None of these

Solution

Probability= (9/21)*(12/20) = (3/7)*(3/5) = 9/35

Correct Option: 3 Best Solution (0)