Charlene decided to ride her bike from her home to visit her friend danny. three miles away from home, her bike got a flat tire and she had to walk the remaining two miles to danny's home. she could not repair the tire and had to walk all the way back home. how many more miles did charlene walk than she rode?

You are standing next to a really big circular lake. you want to measure the diameter of the lake, but you don't want to have to swim across with a measuring tape! you decide to walk around the perimeter of the lake and measure its circumference, and find that it's 400\pi\text{ m}400? m. what is the diameter dd of the lake?