SOLUTION: Please help me solve this. A tank can be filled by a pipe in 3.0 h and emptied by another pipe in 4.0 h. How much time will be required to fill an empty tank if both are running

Question 1098651: Please help me solve this.
A tank can be filled by a pipe in 3.0 h and emptied by another pipe in 4.0 h. How much time will be required to fill an empty tank if both are running?
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39620)   (Show Source): You can put this solution on YOUR website!
Fill Rate, , which means ONE tank's worth filled in TWELVE hours.
Answer by ikleyn(52803)   (Show Source): You can put this solution on YOUR website!
.
See the lesson
    - Using Fractions to solve word problems on joint work
in this site.

Your problem is exactly Problem 5 of this lesson.

You will find there many other similar solved problems with detailed explanations.

RELATED QUESTIONS
A tank can be filled by a pipe in 5.0 h and emptied by another pipe in 6.0 h. How much... (answered by Theo,ikleyn)
A tank can be filled by a pipe in 2.0 h and emptied by another pipe in 3.0h. How much... (answered by ikleyn)
A tank can be filled by a pipe in 3 hours and emptied by another pipe in 4 hours. How... (answered by richwmiller)
Please help me to solve this probblem: A tank can be filled by one pipe in 5 hours and by (answered by ptaylor)
A cistern can be filled by an inlet pipe in 6 hours & emptied by an outlet pipe in 10... (answered by richwmiller)
A cistern can be filled by an inlet pipe in 6 hours & emptied by an outlet pipe in 10... (answered by richwmiller)
A tank can be filled by one pipe stream in 6 hours, and by another pipe stream in 4... (answered by mananth)
A tank can be filled by one pipe stream in 6 hours, and by another pipe stream in 4... (answered by mananth)
Please help me solve this question: Pipe A can fill a tank in 5 h. Pipe B can fill it in... (answered by josgarithmetic,josmiceli)