Question 1098139
<br>Presumably, the intent of the problem is that Joe stops for breakfast before he catches up to Mary.  In that case, we can just say that he eats breakfast before leaving the office, so that he actually gets on the road 1 hour and 15 minutes after Mary.<br>
In 1 hour and 15 minutes at 40mph, Mary drives 50 miles.
Joe's speed is 25 mph faster than Mary's.
So the number of hours it takes Joe to catch up to Mary is 50/25 = 2.
And since Joe left at 8:15, he catches up to Mary at 10:15.