Kathleen can paint a room in 4 hours, and Anthony can paint an identical room in 5 hours. How many hours would it take Kathleen and Anthony to paint both rooms if they work together at their respective rates?
Choose the correct choice from the following choices
A) 8/15  B) 40/9  C) 15/8  D) 9/4  E) 15/4
(1/4 + 1/5)t=2   t= 40/9   Answer: 40/9
<result>B</result>
Kathleen can paint a room in 4 hours, and Anthony can paint an identical room in 5 hours. How many hours would it take Kathleen and Anthony to paint both rooms if they work together at their respective rates?