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QJEEAdv15Ma8f61: JEE Advanced 2015 Mathematics - Class 12 JEEAdv15Ma8f61 Solution: Let n 1 and n 2 be the number of red and black balls,…

Let n1 and n2 be the number of red and black balls, respectively, in box I. Let n3 and n4 be the number of red and black balls, respectively, in box II.

A ball is drawn at random from box I and transferred to box II. If the probability of drawing a red ball from box I, after this transfer, is 13, then the correct option(s) with the possible values of n1 and n2 is(are)

Multiple Choice Options

  • A n1=4 and n2=6
  • B n1=2 and n2=3
  • C n1=10 and n2=20
  • D n1=3 and n2=6

Step-by-Step Verified Solution

JEE Advanced 2015 Paper 2 Offline Mathematics - Probability Question 34 English Explanation

∴ P (drawing red ball from B1) = 13

⇒(n1−1n1+n2−1)(n1n1+n2)+(n2n1+n2)(n1n1+n2−1)=13

⇒n12+n1n2−n1(n1+n2)(n1+n2−1)=13

Clearly, options (c) and (d) satisfy.

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