anversha wrote:

Hi, I have doubt. The question asked for unique 3 letter arrangement. Means the same words should not repeat.

o find the number of different words = 9*8*7 / 3*2*1 = 10. Please share your comments

No, that won't be correct..

By doing 5*4*3/3*2*1, you will get selection of 3 letters and not arrangements..

So you get 10 selection, and each selection has three different letters which can be further arranged in 3! Ways, so 10*3!=60

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