JEE Advanced 2015Paper 2
- Exam
- JEE Advanced
- Year
- 2015
- Paper
- Paper 2
- Subject
- Mathematics
- Chapter
- Probability
JEE Advanced 2015 · Paper 2 · Mathematics · Probability
Let n _ 1 and n _ 2 be the number of red and black balls,...
Let be the number of red and black balls, respectively, in box I. Let 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 , then the correct options(s) with the possible values of is(are)
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 , then the correct options(s) with the possible values of is(are)
Options
- A
- B
- C
- D
Correct answer
C.
Step-by-step solution
Probability = \dfrac{{n}_{1}}{{n}_{1} + {n}_{2}} ⋅ \dfrac{{n}_{1} - 1}{{n}_{1} + {n}_{2} - 1} + \dfrac{{n}_{2}}{{n}_{1} + {n}_{2}} ⋅ \dfrac{{n}_{1}}{{n}_{1} + {n}_{2} - 1} = \dfrac{1}{3}
or
or