#11: Math Party

Alec has been cordially invited to Chimayo’s Math Party. Alec starts off at his home which is 13 miles east and 8 miles south of Chimayo’s house. As Alec steps out the door of his house, he remembers that in any cordial Math Party one must always bring some stream water. The stream is perfectly straight and runs east to west. The stream however is 18 miles south of Alec’s house. Alec being a mathematician easily figures out the least distance he should walk in order to get the water and get to Chimayo’s house. How much did he walk?