Question
A bag contains 20 white and some black balls. If the
probability of drawing a black ball from the bag is 6.25 times that of drawing a white ball, find the number of black balls in the bag.Solution
Given, Number of white balls = 20 Let x be the number of black balls. Total number of balls in the bag = 20 + x Also, the probability of drawing a black ball from the bag is 6.25 times that of drawing a white ball. ⇒ x/(20 + x) = 6.25[20/(20 + x)] ⇒ x = 125 Hence, the number of black balls in the bag = 125.
More Probability Questions
15.99% of 549.99 ÷ 11.17 = ? ÷ 20.15
74.91% of 639.95 – 599.98% of 45 + 119.987 = ?
(4.88 × 5.76)2 - ?2 = 39.89 × 19.86
- What approximate value will come in place of the question mark (?) in the following question? (Note: You are not expected to calculate the exact value.)
- What approximate value will come in place of the question mark (?) in the following question? (Note: You are not expected to calculate the exactvalue.)
(1800.23 ÷ 29.98) + (816.32 ÷ 23.9) + 1634.11 = ?
1449.98 ÷ 50.48 × 10.12 = ? × 2.16
36.05 × 5.02 + 12.052 = ? + 9.09 × 4.04
(31.9)3 + (34.021)² - (16.11)3 - (42.98)² = ?
