Join the Car Talk Community!

The Perfect Square Dance!

The Puzzler


RAY: This was from my ballroom dancing series and it was sent in by Dennis Vogel.

Sally invited 17 guests to a dance party at her estate in the Hamptons. She assigned each guest a number from 2 to 18, keeping 1 for herself.

At one point in the evening when everyone was dancing, Sally noticed the sum of each couple's numbers was a perfect square. Everyone was wearing their numbers on their clothing.

The question is, what was the number of Sally's partner?

Here's a reminder: a perfect square is attained by squaring, or multiplying by itself, an integer. So four is a perfect square of two. Nine is a perfect square of three. Sixteen is a perfect square of four. So these numbers are adding up to either 4, 9, 16, 25, etc. And the question is, with the information you have available to you, what's the number of her partner?

Think you know? Drop Ray a note!

[ Car Talk Puzzler ]

Support for Car Talk is provided by:

Donate Your Car,
Support Your NPR Station

...and get a tax break!

Get Started

Find a Mechanic


Go



Submit


Rocket Fuel