**Had
by an ad?**

A hamburger chain advertises that its 1/2-pound hamburgers are 50% bigger than its competitor's 1/3-pound hamburgers. Is this false advertising? [From CCTT writing institute, 6/01]

**Approaches**

50%(or 1/2) of 1/3 pound is 1/6 pound. 1/6 pound more than 1/3 pound is 1/2 pound. So it's not false advertising.

What's wrong with these other approaches, which claim the opposite?

50% (or 1/2) of 1/2 is 1/4. 1/2 - 1/4 = 1/4, which is less than 1/3. So 1/2 is more than 50% more than 1/3, and it is false advertising.

If one number is 50% more than the other, is the other 50% less than the one?

50% (or 1/2) of 1/3 is 1/6. 1/6 is not nearly so big as 50%, or 1/2. So the 1/2-pound hamburger is not nearly 50% bigger than the 1/3-pound hamburger. It is false advertising.

Why are you using 50% in two different ways?

**Your
experience**

Have you used this problem with a class and seen approaches other than(or more specific than) those mentioned above? Or do you have other comments or criticisms or stories? If so, please tell us!

*Last updated 30 November, 2004*