Frank Morgan's Math Chat


November 1, 2001

The Ideal TV

Old Challenge. What is the ideal size and shape for a TV set?

Answer. In his winning answer, Joseph Fine says that the ideal shape for a TV set would be a virtual spherical surface similar to the inside of a planetarium. The ideal may already have been implemented as a direct retinal projection TV in which images project directly into the eye, with no screen at all. See

QUESTIONABLE MATHEMATICS. Joshua Green noticed a Burger King sale:

Cheeseburger: $.49
Double Cheeseburger: $.99
Triple Cheeseburger: $1.49

He wonders "why two cheeseburgers are cheaper than one double cheeseburger, and three cheeseburgers are cheaper than one triplecheeseburger, when the individual burgers have more bun but the same amount of meat?"

Readers are invited to submit more examples of questionable mathematics.

New Challenge. Is there any valid explanation for the above cheeseburger sale?

Copyright 2001, Frank Morgan.

Send answers, comments, and new questions by email to, to be eligible for Flatland and other book awards. Winning answers will appear in the next Math Chat. Math Chat appears on the first and third Thursdays of each month. Prof. Morgan's homepage is at

THE MATH CHAT BOOK, including a $1000 Math Chat Book QUEST, questions and answers, and a list of past challenge winners, is now available from the MAA (800-331-1622).