Answer:
Step-by-step explanation:
1) we know that
Sally can paint the wall in 54 minutes
so
The 100% of the wall ------> she can paint in 54 minutes
by proportion
calculate how much is the percent of the work in 36 minutes
That means
Sally in 36 minutes can paint the 66.67% of the wall
2) Sally and Ethan work together, they can paint the wall in 36 minutes
so
Ethan in 36 minutes can paint (100%-66.67%)=33.33%
by proportion
Calculate how much time does it take for Ethan to paint the wall by herself