Grace spent 4 1/2 hours restoring this time makes up 6% of the time needed how much time is needed to fully restore the boat

4.5h=6t/100

6t=100(4.5h)

t=100(4.5h)/6

t=75

It takes a total of seventy-five hours to restore the boat. 

If 4.5 hours is 6% of restoring the boat, then Grace would need to spend 27 hours to fully restore the boat. 

You can find this by multiplying 100 by 6% to find the amount of times you need to do the same amount of work you've already done to complete the project.

This leaves you with 6, which you can multiply with 4.5 to get 27 hours.