Tony has to run several errands in a day.  He needs to drive 10 miles to get groceries, 15 miles to get a haircut and 5 miles to go to a doctor's appointment.  How many miles will Tony have driven when he is halfway through driving around for his errands?
First, we need to find the total number of miles Tony will be driving by adding 10+15+5=<<10+15+5=30>>30 miles in total.
To determine the halfway point, we simply divide the total number of miles by 2, performing 30/2=<<30/2=15>>15 miles driven when Tony is halfway done.
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