The probability of selecting a green marble at random form a jar that contains only green, white and yellow marbles is 1/4. The probability of selecting a white marble at random form the same jar is 1/3. If this jar contains 10 yellow marbles. What is the total number of marbles in the jar?

Let the number of green marbles be x and the number of white marbles be y


Total number of possible outcomes, n(S) = x + y + 10



Probability of green marbles = 1/4



x + y + 10 = 4x


3x y 10 = 0 -------------(i)


Probability of white marbles =



x 2y + 10= 0 -------------(ii)


Solving eq. (i) and (ii), we get


x = 6 and y = 8


Thus, total number of marbles in the jar = x + y + 10 = 6 + 8 + 10 = 24


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