Question 581296
Let x=amount of time it takes Steve to clean the room working alone
Then Steve works at the rate of 1/x room per hour

Beverly works at the rate of 1/4 room per hour

Beverly and Steve working together works at the rate of 1/(4/5) =5/4 room per hour (48 min=4/5 hr and we are working in hours)

Soooo, our equation to solve is:
(1/4)+(1/x)=5/4  multiply each term by 4x
x+4=5x
4x=4
x=1 hour----amount of time it takes Steve to clean the room working alone.

CK
in 4/5 of an hour Steve cleans 4/5 th of the room
in 4/5 of an hour Beverly cleans(1/4)(4/5) =1/5 of the room
1/5+4/5=1 (room that is)

Hope this helps---ptaylor