answer: 80%
Step-by-step explanation:
to find out what percent he completed, divide what he has completed by the total number
20/25 = 0.8
now, multiply the decimal by 0.8 and multiply by 100 to turn into a fraction
0.8 x 100 = 80
so, he answered 80% so far.
i hope this helped and have a great day! if you need any further assistance with this specific question or i made any mistakes, please let me know!