Wait, what?

Here’s a question in my textbook:

The weight of a person’s skin is related to body weight by the equation s = 0.0625w, where s is skin weight and w is body weight.

If a person calculates skin weight as 9.75 pounds, what is the person’s body weight?

Um. Really? That’s the direction you want students to go with this equation? How many people in the world happen to know how much their skin weighs but have never stepped on a scale before?

That, and, the real wow factor is going from 156 pounds on the scale to almost 10 pounds of skin. That’s a little crazy.