Need some help again with another word problem...I hate these things....here is the problem: An efficient heater can warm the entire gymnasium in 3 hours. An older, less efficient heater requires 8 hours to heat the same space. How long would it take to heat the gymnasium if both heaters worked together?

Question

Need some help again with another word problem...I hate these things....here is the problem:  An efficient heater can warm the entire gymnasium in 3 hours.  An older, less efficient heater requires 8 hours to heat the same space.  How long would it take to heat the gymnasium if both heaters worked together?

anonymous · Answer

2.1818

anonymous · Answer

if you had two of the three hour heaters, it would take 1.5 hours right
so y/3+y/3=2y/3 or 1.5
following 
y/8+y/3= 11y/24 or 2.1818 makes sense because its less than the three hour alone

anonymous · Answer

are you using / to mean dividing?  Sorry...someone else had helped me with a different problem and when they used / it meant something else.  Thanks for your help!  I appreciate it