You can
put this solution on YOUR website!The trick is to find the number of hours where the two companies would charge the same amount. So if the expression for HL is

and the expression for QM is

, you need to set these two expressions equal to each other and solve for h:
So now we know that at 4 hours, it doesn't matter which company you choose:

and

.
From the first two parts of the problem, you know that QM is a better deal at some point less than 4, and HM is a better deal at a point greater than 4.
So your inequality becomes: QM is a better deal if

. Notice that we don't include the 'or equal to' in the inequality because we are looking for QM to be a BETTER deal. If

then QM and HL offer the same deal, and the same is not better.
This brings up another point. Could we have said that QM is a better deal if

? Actually, we can't answer that with the information given, because we don't know whether either company charges a fractional hourly rate for a fraction of an hour used.
If, for example, QM charges $55 for every hour or part of an hour, i.e. 3.5 hours is the same fee as 4 hours, then

would be the same as

. On the other hand, if they actually charge

for 3.5 hours of use, then the only acceptable answer is

.