Question
A bag contains 13 white and some black balls. If
the probability of drawing a black ball from the bag is twice that of drawing a white ball, find the number of black balls in the bag.Solution
Number of white balls = 13
Let x be the number of black balls.
Total number of balls in the bag = 13 + x
Also, the probability of drawing a black ball from the bag is twice that of drawing a white ball.
⇒ x/(13 + x) = 2[13/(13 + x)]
⇒ x = 2 × 13 = 26
Hence, the number of black balls in the bag = 26
More Probability Questions
I. Â 3y2Â + 13y - 16 = 0
II. 3x2 – 13x + 14 = 0
Solve the quadratic equations and determine the relation between x and y:
Equation 1: 31x² - 170x + 216 = 0
Equation 2: 22y² - 132y + ...
I. 20y² - 13y + 2 = 0
II. 6x² - 25x + 14 = 0
I. 2y2Â + 11y + 15 = 0
II. 3x2Â + 4x - 4= 0
In the question, two equations I and II are given. You have to solve both the equations to establish the correct relation between 'p' and 'q' and choose...
I. 5x² = 19x – 12
II. 5y² + 11y = 12
I. x2 – 13x + 40 = 0
II. 2y2 – 15y + 13 = 0Â
I. x² + 3x – 154 = 0
II. y² + 5y – 126 = 0
I. x² + 11x + 24 = 0
II. y² + 17y + 72 = 0
I. 4p² + 17p + 15 = 0
II. 3q² + 19q + 28 = 0
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