Question 909174
A tank can be filled by an inlet pipe in 7 hours. While a drain pipe can empty
the tank in a matter of 11 hours. If for the <font color = "red"><b>first hours</font></b>, the drain pipe was left 
open while the inlet pipe was filling it, how much longer would it have taken 
the inlet pipe to fill the tank full if the tank was emptied at the start?

<pre>
Notice the two words which I made red above.  There must be a number between
those two words in order for us to be able to work the problem.  You can restate
the problem, including the number that was supposed to go between those two
words, in the thank-you note form below and I'll be glad to show you how to do
the problem.

Edwin</pre>