It would take john 6 hours to paint a room by himself. It would take Tom 18 hours to paint the same room by himself. Of john and tom work together, each at his individual rate, how many hours will it take the to paint the room.

4h 30min

Step-by-step explanation: Theoretically, if X= Number of hours required to paint the room,

X(1/6+1/18)=1

X(3/18+1/18)=1

X(4/18)=1

X(2/9)=1

2/9X=1

X=9/2h, or 4 1/2 h

you can first factor out the n to get n(1+5). we know that 1+5 is 6, so we just have 6n.