Jonathan and Bill need to stack firewood. Jonathan can stack 130 pounds of firewood in 2 hours. Bill can stack 150 pounds of firewood in 3 hours. How long will it take them to stack 400 pounds of firewood if they work together (round to the nearest hundredth)?

Answer 1

J can stack 400 lbs in 2*400/130 = 6.15 hrs
B can stack 400 lbs in 3*400/150 = 8 hrs

1/X = 1/6.15 + 1/8
X = 3.48

Answer 2

5.71 hours