# So, how many codes per peptide?

### If there are 2.19 × 10^{99} distinct 165-nucleotide sequences, but only 9.00 ×
10^{68} distinct 53-amino-acid peptides, how many ways (on average) can each peptide be coded?

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- I need a hint ... : you want codes per peptide, so divide the number of nucleotide
sequences by the number of peptides.

- ...another hint ... : 2.19 × 10
^{99}/ 9.00 × 10^{68}= ?

- ...another hint ... : divide the numbers, subtract the zeros.

#### I think I have the answer: 0.22 × 10^{31} ,
a.k.a. 2.2 × 10^{30}.

Wow! 2.2 × 10^{30} is 2 million trillion trillion. That's the number of ways (on average)
that any given 53-AA protein could be coded. Ten million times more than the number of atoms in a mol.
Once again, if your mind isn't boggled, better get it checked out.

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