if in a code language , cat=12 , tiger= 30 , then elephant =

Please give the options too. Because I have a logic and according to that the answer is 72.
CAT has 3 letters -> 3*4=12
TIGER has 5 letters -> 5*6=30
ELEPHANT has 8 letters -> 8*9=72
n*(n+1) is solution where n is number of letters in the word.

@badrinath reddy, how did you come to that conclusion of yours ?

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