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Gurudev said – Thu, 16 Jul 2009 05:52:01 -0000 ( Edit Link )

Question : A number x is chosen at random from the set of positive integers less than 10. What is the probability that (9/x) > x ?

A: 1 / 5 B: 2 / 9 C: 1 / 3 D: 2 / 3 E: 7 / 9

A bag contains 3 red, 4 white, and 5 blue marbles. Jason begins removing marbles from the bag at random, one at a time. What is the least number of marbles he must remove to be sure that he has at least one of each color?

A: 3 B: 6 C: 8 D: 10 E: 12

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tomal_ti said – Thu, 16 Jul 2009 08:23:44 -0000 ( Flag Edit Mark / Unmark Best Link )

Question 1 : Ans B

Question 2: ans: D
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tomal_ti said – Thu, 16 Jul 2009 08:25:32 -0000 ( Flag Edit Mark / Unmark Best Link )

explanation 1 : 9/x > x x*x <9 x< 3 so s can be 1 or 2 so , probability = 2/9
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Gurudev said – Thu, 16 Jul 2009 19:15:04 -0000 ( Flag Edit Mark / Unmark Best Link )

Thanks for ur kind suooprt.can u pls explain2 nd also
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1. deepa mittal said – Thu, 23 Jul 2009 07:41:47 -0000 ( Flag Edit Link )
  
  If Jason takes out 9 marbles, it is possible that 4 are white and 5 are blue. So in order to make sure that there is atleast one of each colour, Jason needs to remove atleast 10 marbles.
  
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tomal_ti said – Fri, 17 Jul 2009 08:02:51 -0000 ( Flag Edit Mark / Unmark Best Link )

if we take 9 marbles then it can be white and blue ‘cause 4+5=9 . so if we want to take at least one marble of each kind we need to take at least 10 marbles .
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gunjan_shah said – Tue, 21 Jul 2009 08:52:12 -0000 ( Flag Edit Mark / Unmark Best Link )

I think the answer to your second question should ‘A’. because you intend to take ‘LEAST’ number of marbles not the ‘MOST’. So, first you take red then blue and then white [1+1+1 = 3] so answer should be 3. If question was to take the MOST no. of marbles then the answer would have been ‘10’.

Please comment if i am missing something here.
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1. deepa mittal said – Thu, 23 Jul 2009 07:40:52 -0000 ( Flag Edit Link )
  
  The question asks for the least number of marbles that must be removed to be sure that there is at least one of each color. If he takes out 9 marbles it is possible that 4 are white and 5 are blue. So in order to make sure that there is atleast one of each colour, Jason needs to remove atleast 10 marbles.
  
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amanpreet055 said – Sat, 25 Jul 2009 18:38:05 -0000 ( Flag Edit Mark / Unmark Best Link )

can you tell me the answer , what is the answer for the second question.. i meaan real answer
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1. deepa mittal said – Mon, 27 Jul 2009 10:51:23 -0000 ( Flag Edit Link )
  
  The correct answer is 10.
  
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