Calculate the probability of finding at least one terminator

Calculate the probability of finding at least one terminator codon in the +1 frame of a DNA segment 90bp long.

Note: yes, this is a challenging probability problem. So, do not worry if it seems impenetrable. Look at the clues and see if you can work it out. The objective is for all to understand that in random DNA a STOP codon will pop up sooner or later.

Answer options are: 0.24, 0.10, 0.29, 0.53, 0.76

Solution

Answer:-Option c 0.29

EXPLANATION :-The probability of finding one terminator codon in DNA of 90bp long would be

Since there are 64 codons out which 3 are terminator codons. The 90bp DNA would consists of 30 codons and probablity of having atleast one terminator codon in 90bp DNA would be almost 0.29. 1/30=0.33