Final answer:
The likely percentages of thymine and guanine in wheat DNA are: Thymine: 27% and Guanine: 23%.
Step-by-step explanation:
In DNA, the amount of adenine is equal to the amount of thymine, and the amount of guanine is equal to the amount of cytosine. This is known as Chargaff's rule.
Since the relative percentages of adenine and cytosine in wheat DNA are 27% and 23% respectively, we can infer that the percentages of thymine and guanine will also be 27% and 23% respectively.
Therefore, the likely percentages of thymine and guanine in the DNA of wheat are: Thymine: 27% and Guanine: 23%.