Math in the Real World

Date: 2/19/96 at 9:2:54
From: Helder Caixinha
Subject: Mathematics and our lives

I would like to know some examples of mathematical applications in 
the real world.  That is, mathematical concepts that we contact 
every day for example in a newspaper,in TV....

With my best regards,

   Paula Pires, high school teacher

Date: 6/21/96 at 9:42:28
From: Doctor Patrick
Subject: Re: Mathematics and our lives

Hi!  Here are some ways I can think of that math is used in real 
life:

Area is used to figure out how much of something will be needed to 
cover something else - how much wallpaper you need for your room, 
how big a carpet will fit into the room,...

Volume is used in the same way, except for 3D objects - how much 
water will fill a pool for example.

Trig functions are used all the time for navigation - including in 
the space program.  They can also be used to figure out the height 
of buildings (or trees, or mountains) by knowing how far you are 
from the object and what the angle is from where you are on the 
ground to the top of the object you want to measure.  

 *c
 |\        If you know the distance (x) and the angle (y) you can 
 | \       find the height (h).  Since h/x=tan(y) you can plug in 
h|  \      the numbers you know and solve for h.  This is very 
 |   \     useful for figuring out the height of object that might 
 |   y\    otherwise be too big, or awkward to measure otherwise.  
 ------*   You can also use this to figure out how far you are 
    x      from someplace if you know how high it is.  I know 
           people who have used this when they go camping and 
hiking.  They find out what the height of a large mountain near 
where they are going to be is, and then using some math they can 
always figure out how far from it they are to give them a sense 
of direction.

Math is used all the time in accounting and banking and anything 
else dealing with money.  Natural logs, for instance, are used in 
calculating compound interest (although I can't really remember 
how that works at the moment).

Math is used by train, boat, and plane companies to figure out how 
long it will take to get somewhere at a given speed, and how much 
time will be saved or lost because of the wind or water speed.

I hope this will be of help.  If you have any more questions 
please write back to us.

-Doctor Patrick,  The Math Forum