Q6 of 68 Page 330

If 2nC3: nC3 = 12 : 1, find n.

Given: 2nC3: nC3 = 12 : 1


To find: n=?


2nC3: nC3 = 12 : 1


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⇒2n-1=3(n-2)


⇒2n-1=3n-6


⇒n=6-1=5


Ans:n=5


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