Math with ParenthesesDate: 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 |
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