Basic Math Problem - Need Help

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mevans154

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OK, all you engineers. I have a basic math problem here.

The older engineers in the office get one answer and the younger engineers get a different answer

6/2(1+2)=??

What is the correct answer?

 
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THey get 9 don't they.
Yes, the older engineers say the answer is 9, and the younger engineers say the answer is 1

The older engineers say once you do the math in the brackets (2+1), you then work left to right.

6/2(1+2)= 6/2*3

6/2=3

3*3=9

So what is the right answer??

 
and if you use some calculators you get 1. The math experts out there still argue about this.

Using the () to act as * tends to mess people up.

 
^ please my dear aunt sally

apparently some of you better find an older engineer to cling to :p

 
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Perform math left to right --> 6/2(3) = 3(3) = 9


Or, do numerator and denominator math first ---> 6/2(3) = 6/6=1


If it's numerator / denominator, the numerator is 6 and the denominator is 2. Answer is 9. If the 2 AND 3 were the denominator in this linear layout, there would be additional parentheses around the 2 AND 3.

6/2(3) = 9

6/(2(3)) = 1

 
The answer is 9. In the Hierarchy of order of operations, multiplication/division comes before addition and subtraction. In the same vein, exponentiation comes before multiplication/subtraction. As I recall the order of operations, it is exponentiation------- multiplication/division-------addition/subtraction.

So, divide 6/2=3. THEN work the problem INSIDE the brackets (2+1=3). Restate the problem, 3*3=9

That is the way that I remember it. It has nothing to do with what direction, i.e., left to right you solve the problem-- it is the hierarchy of operations that is accomplished first. I am not an algebra teacher, however, this is how I recall it being done.

Yes, I would be in the more seasoned engineer group!

 
There is no *right* answer... this one has been around the interwebs for quite a while. It doesn't matter what a calculator, Excel, or Wolframalpha gives for the result because each one is based on its own interpretation of the "rules".

There's always confusion about the difference between unary and binary operations and the difference between "/" and "÷". As snickerd3 writes, clear up any ambiguity with parentheses!

 
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