New Enroll in RBI Grade B New Batch - Starts on May 21

    Question

    A box contains 6 red, 4 blue, 2 green and 4 yellow pencils.

    If two pencils are picked at random, what is

    the probability that one is blue and one is yellow?
    A 3/19 Correct Answer Incorrect Answer
    B 2/11 Correct Answer Incorrect Answer
    C 4/15 Correct Answer Incorrect Answer
    D 2/15 Correct Answer Incorrect Answer
    E none of these Correct Answer Incorrect Answer

    Solution

    Total number of pencils = 6 + 4 + 2 + 4 = 16 Let S be the sample space. Then, n(S) = number of ways of drawing 2 pencils out of 16 = 16C2= `(16xx15)/(2xx1)` ` ` = 120 Let E= event of drawing two pencils so that one is blue and one is yellow n(E) = 4C1 X 4C1= 4 `xx` 4 = 16 [if gte msEquation 12]>∴ [if !msEquation]--> [endif]-->P (E) = `(n(E))/(n(S))=16/120=2/15`

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