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D A bag contains 50 balls, some of them are white, some are bluand some are red. The number of white balls is 11 times thenumber of blue balls. The number of red balls is less than thenumber of white balls but more than the number of blue ballsIf one ball is taken out at random from the bag, what is theprobability that it is red? |
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Answer» The probability of getting the red ball from the bag is 7 / 25 Let the number of blue balls be ' x ' According to question, The number of WHITE balls is 11 times the number of Blue Ball Therefore, number of white balls = 11x So, Blue balls + White balls = x + 11x = 12x ALSO, it is given : The number of red balls is less than the number of white balls and is more than the number of Blue Balls, that is, Blue balls < Red balls < White balls x < number of red balls < 11x Since the total number of balls are 50, The POSSIBLE sum of blue and white balls are : 12, 24, 36, 48 If the sum is 12, Blue ball = 1 [ x = 1 ] White = 11×1 = 11 Red ball = 50 - 12 = 38 Since Number of Red ball > White ball It does not satisfy the given condition if sum is 24 Blue ball = 2 [ x = 2 ] White = 11×2 = 22 Red ball = 50 - 24 = 26 Again Since Number of Red ball > White ball It does not satisfy the given condition Taking sum = 36 Blue ball = 3 [ x = 3 ] White = 11 * 3 = 33 Red ball = 50 - 36 = 14 Since Number of Red ball < White ball and also Number of Red ball > Blue ball So this SATISFIES the condition Taking sum = 48 Blue ball = 4 [ x = 4 ] White = 11 * 4 = 44 Red ball = 50 - 48 = 2 Since Number of Red ball < White ball but Number of red ball < Blue ball So, it does not satisfy the given condition Therefore third option where total sum is 36 is the only correct possibility. So, Number of blue balls = 3, Number of white balls = 33 Number of Red balls = 14 We know , Total number of ball = 50 Number of red ball = 14 Probability = Number of possible OUTCOMES / Total number of outcomes Probability of getting red ball = 14/50 = 7/25 Hence, The probability of getting red ball from the bag is 7/25
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