A lifeguard can swim at a speed of 6 feet per second and run at a speed of 10 feet per second. The lifeguard is standing at the edge of a beach, looking at the ocean to the south. The lifeguard sees a drowning child in the ocean 100 feet east (down the shore) and 80 feet south (out at sea). How far should the lifeguard run before they start swimming?
The lifeguard can run at a speed at 10 feet per second, so if the shore is 100 feet away (before the ocean starts and he has to swim) you do 100 x 10 to get 1000 feet :D