Q19 of 25 Page 15

A bag contains 5 red balls and some blue balls. If the probability of drawing a blue ball is double that of a red ball, determine the number of blue balls in the bag.

To Find: The number of blue balls


Given: Number of red balls = 5


P(blue) = 2 P(Red)


Concept Used:



Explanation:


Let the number of blue balls = x


Total number of balls = blue balls + red balls


Total balls = x + 5


The probability of drawing a red ball, P(Red)



The probability of drawing a blue ball, P(blue)



Now,




x = 10


Therefore, x = 1, as it cannot be negative.


Hence, the number of blue balls is 10.


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