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Outline Mathematics
Arithmetic Word Problems

Food of a Lifetime

Here's a problem to tackle:

 

How many pounds of food will you eat in a lifetime?

A clue: An elephant weighs about 10,000 pounds. In your lifetime, you will eat the equivalent weight of 6 elephants.

Solution


Copyright © 1996-2009 Alexander Bogomolny

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Solution

 

How many pounds of food will you eat in a lifetime?

A clue: An elephant weighs about 10,000 pounds. In your lifetime, you will eat the equivalent weight of 6 elephants.

(In the text below, some words are omitted. These have been underlined. Click just above the line. See what happens.)

First, let's make it clear that the problem in fact talks of an average person. A particular you will almost certainly eat either more or less than the amount that is expected as the problem's answer. Still, the specific you who is going to find that amount will, in all likelihood, eat close to it during your lifetime.

If an average elephant weighs 10,000 pounds and you, in your lifetime, will gobble the equivalent of 6 average elephants then, when all is said and done, you will consume 6×10,000 pounds of food which comes to pounds.

There is a fine point to make. The computed quantity of 60,000 is the exact product of two given numbers, , and . However it only represents approximately the amount of food you are going to consume in your .

Come to think of it: a quarter pounder is quite a filling serving. Assume you consume nothing else, but subsist on quarter pounders alone. How many quarter pounders will you eat in your lifetime? Why, there are quarter pounders in a pound of which you will consume 60,000. All in all, it comes to 4×60,000 = quarter pounders. This, too, is an exact amount that approximately represents an expected quantity.

Assume that an average person lives, say, 80 years and a year has 365 days in it, give or take. Under this assumption you will have 80×365 = days to enjoy your food. (I discount the happiest toothless years of your life.) If our calculations are correct, to live up to our expectations you'll have to consume 240,000 / 29,2008 quarter pounders a day. This is an approximate number and this is why we used "" instead of " " that stands for the exact equality. 8 hamburgers a day! The fast food chains would be happy, hmm.

References

  1. E. Charlesworth, 225 Fantastic Facts Math Word Problems, Scholastic, 2001

Copyright © 1996-2009 Alexander Bogomolny

33062054Page copy protected against web site content infringement by Copyscape


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