City B is 10 miles downstream from city A and on the

Last updated: 7/17/2022

City B is 10 miles downstream from city A and on the opposite side of a river half a mile wide. Mary will run from city A along the river for 6 miles, and then swim diagonally (i.e., along a straight line) across the river to city B. If she runs at 8 miles per hour and swims at three miles per hour she will reach City B after hours. Assume that the current is negligible.