COMEDK · Maths · 4. Permutation Combination
In how many ways can 4 red, 3 yellow and 2 green discs be arranged in a row, if the discs of the same colour are indistinguishable?
- A 1200
- B 1220
- C 1240
- D 1260
Answer & Solution
Correct Answer
(D) 1260
Step-by-step Solution
Detailed explanation
Total number of dises are \(4+3+2=9\). Out of 9 dises, 4 are of the first kind (red) 3 are of the second kind (yellow) and 2 are of the third kind (green). Therefore, the number of arrangements \(=\frac{9 !}{4 ! 3 ! 2 !}=1260\)
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