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A function `f` from integers to integers is defined as `f(x)={(n+3, n "is odd"),(n/2 , n "is even"):}`. If `k` is an odd integer and `f(f(f(k)))=27` then the sum of digits of `k` isA. `3`B. `6`C. `9`D. `12` |
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Answer» Correct Answer - B `kepsilon` odd `f(k)=k+3` even `f(f(k))=(k+3)/2` Case 1 if `(k+3)/2epsilon` odd `27=(k+3)/2+3impliesk=45` (not possible) Case 2 if `(k+3)/2 epsilon` even `27=f(f(f(k)))=f((k+3)/2)=(k+3)/4` `implies k=105` sum digits `=6` |
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