Imagine that a 5 ft 6 in woman walked around the earth at the equator. The path traced by the top of her head is how much longer (to the nearest foot) than the path traced by the soles of her feet?
Solution: The path along which the woman’s feet moves is a circle, so we need to use the formula for the circumference of a circle, C=2(pi)r. The woman’s feet move along the circumference of the earth ( 2(pi)r, where r is the
earth’s radius), while her head moves along a circle with a radius of r + 5.5 feet. Thus, feet |