Answer:
30% is guanine
Step-by-step explanation:
This is because Chargaff’s rule says that the DNA molecule should have an equal ratio of pyrimidine (cytosine and thymine) and purine (adenine and guanine).
If 20% is Adenine then that means Thymine is 20%, they both add up to 40% leaving us with 60%
Once again since they have to be equal ratios that means what remain is the 30%.
Extra Note:
Hope this helped =)