What age do YOU think is old?

I just saw this in the IntMath Newsletter I subscribe to...

QUOTE

Here's an age equation that's pretty accurate:

OldAge = 10 * √NowAge

When you're 16, old people are 40. When you're 50, old people are 70, and when you're 100, you know you're old!

UNQUOTE

Hat Tip to Murray from

http://www.intmath.com/blog/letters/intmath-newsletter-quadratic-graphs-cymath-food-learning-11234