How To: Convert from gallons to quarts, pints and cups in basic math

Need to know how to express gallons in quarts, pints and cups? From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps. With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to convert between gallons, quarts, pints and cups.