Fraction/Percentage word problem

Question

A storm in 2015 caused one of the largest power outage events ever recorded in Chilliwack. BC Hydro crews restored power to 40% of the customers within the first two hours. Of the customers still in the dark, one- quarter of them got the power back over the next three hours. At this point, 9000 customers were still without power. What was the total number of customers in Chilliwack who lost power during the outage

Answer 1

x-.4x=.6x

.6x-(.25*6x)=.45x=9000

/.45=20,000