ap physics
posted by Zoe .
I need some help with the following problems. I got no idea how to do it...PLEASE HELP!!!!THANKS A LOT!!
A hunter is standing on flat ground between two vertical cliffs that are directly opposite one another. He is closer to one cliff than the other. He fires a gun and , after a while, hears three echoes. The second echo arrives 1.6s after the first, and the third echo arrives 1.1s after the second. Assuming that the speed of sound is 343m/s and that there are no reflections of sound from the ground, find the distance between the cliffs.

The first echo is from the nearer clift. The second is from the farther clift. The third is from the nearer clift (second echo on that path from the farther clift).
Let N be the distance from nearer clift.
Let F be the distance from the farther clift.
2N=v t
2F=v(1.6+t)
2F+2N=v(1.1+1.6+t)
Three equations, you can solve for all three, and you want to find F+N.