To start finding the answer to this problem, you should put both of these numbers into decimal form. 8 tenths=0.8. 5 hundredths=0.05. Now you just subtract like you would with any other decimal subtraction problem. 0.8-0.05=0.75.
Your answer is 0.75. In fractional form, this would be 3/4. In percent form, this would be 75%.