Posted by **Tamie** on Thursday, April 25, 2013 at 5:40pm.

There is a mathematical relationship between an airplane’s weight x and the runway length required at takeoff. For certain types of airplanes, the minimum runway length L in thousands of feet may be modeled by L(x) = 1.3 ln x, where x is in thousands of pounds. a) Estimate the runway length needed for an airplane weighing 10,000 pounds. (b) Does a 20,000-pound airplane need twice the runway length that a 10,000-pound airplane needs? Explain