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Math with Parentheses


Date: 10 Mar 1995 11:50:47 -0500
From: Michael Ernest Kallsen
Subject: math

Is there an easier way to do math with parenthesis?
Example:  2+8(8x4)-6 divided by 4 = ?
I've learned that you do powers, parenthesis, multiplication, 
division, add, and subtraction. 

Michael


Date: 13 Mar 1995 21:20:45 -0500
From: Dr. Ethan
Subject: Re: parenthesis

Hey Michael,
        I must say I am not sure how much of an easier way you are 
looking for.  The method you said, "powers, parenthesis, 
multiplication, division, add, and subtract" is the best one that I 
know.  I will say that as you you use them more, they will become 
second nature.  Believe me, in the long run parentheses make
things easier.  For instance:

4(3+5+7+1+8+3)  is a lot shorter than

4*3 + 4*5 + 4*7 + 4*1 + 4*8 + 4*3 
        [The * means multiply]

So in that way, parentheses make things easier.

In fact, in your example I would use one more set of parentheses.  I 
would write:

(2+8(8*4)-6)/4
				[The / means divide]

and the answer that I get is 63 by doing it this way.

Because there are no powers, we can go straight to the parentheses.  
Do the inner parentheses first.  8*4 is 32 so we have:

(2 + 8*32 -6)/4

Now we do the second parentheses.  Within the second parentheses 
we have 2+ 8*32 - 6.  So we do multiply first and get 2+256 - 6.   
Then we add and get 258 -6.  Then we subtract and get 252. 

Now we have finished the second parentheses and we are left with
252/4.  So we divide and get 63.

Write back if you want more help and we would be glad to help more.

Ethan, Doctor On Call
    
Associated Topics:
Middle School Algebra

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