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Goldman Sachs Probability Question

Goldman Sachs Probability Question - 13 November

There is a dressing drawer which contains the following colored socks in pairs: Purple, Magenta, Crimson, White, Yellow and Turquoise. Now, the socks are paired and each pair is together in the matching set. There is no light in the room and you open the drawer and pick up a pair. Then, without noticing any color, you keep them back and pick up again.

Can you calculate the probability that the pair of socks was Yellow both the times?

For Solution : Click Here


  1. Although it seems too simple for a "task" at probability theory, I can't see any other solution than the obvious one:
    1/6 * 1/6=1/36
    Probability of choosing yellow (or whatever color) 1 out of 6
    Second try (after replacement) still 1/6.

  2. Whenever two events are independent, we calculate the probability of both occurring as:
    P(A and B) = P(A) * P(B)
    P(Yellow) = 1/6
    P(Yellow and Yellow) = P(Yellow) * P(Yellow)
    = 1/6*1/6
    = 1/36