Answer: 12 hours
Step-by-step explanation: For this problem we will write a percent equation to solve for 100% and how many total hours it will take angel to finish the entire project.
Lets write a equation to solve for w, total amount of hours.
9/w = 75/100
9/w x w = 75/100 x w
9 = 75w/100
9 x 100/75 = 75w/100 x 100/75
w = 12
So, it will take Angel 12 hours to finish his entire project.