Puzzle:
Probability of Picking socks of same color.
There are 5 pairs of Black Socks and 5 pairs of White Socks. What is the probability to pick a pair of black or white socks when 2 socks are selected in random.
Probability of Picking socks of same color.
There are 5 pairs of Black Socks and 5 pairs of White Socks. What is the probability to pick a pair of black or white socks when 2 socks are selected in random.
Answer:
Number of Ways to pick 2 socks from 20 socks = 20C2 = (20*19)/2 = 190
Number of Ways to pick 2 Black socks from 10 socks = 10C2 = (10*9)/2 = 45
Probablity of picking 2 Black socks = 45/190
Similarly ,
Probablity of picking 2 White socks = 45/190
Probablity of picking 2 socks of same color = 45/190 + 45/190
= 9/19
Number of Ways to pick 2 Black socks from 10 socks = 10C2 = (10*9)/2 = 45
Probablity of picking 2 Black socks = 45/190
Similarly ,
Probablity of picking 2 White socks = 45/190
Probablity of picking 2 socks of same color = 45/190 + 45/190
= 9/19
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