Order Of Operations Equation

MathMind

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Hi there,

I need some assistance with answering the following equation. That line is my flimsy attempt at making it a fraction..

\(\displaystyle \displaystyle{\dfrac{3 * \frac{27}{12} + 2^4}{2 * 3^3 - 2 * \sqrt{25}}}\)

I followed PEMDAS as best I could, and got the answer of 91/160... I think I am not doing it correctly.
 
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Hi there,

I need some assistance with answering the following equation. That line is my flimsy attempt at making it a fraction..

\(\displaystyle \displaystyle{\dfrac{3 * \frac{27}{12} + 2^4}{2 * 3^3 - 2 * \sqrt{25}}}\)


I followed PEMDAS as best I could, and got the answer of 91/160... I think I am not doing it correctly.

It is incorrect.

Please share your work - so that we can help you catch your mistake.
 
Hi there,

I need some assistance with answering the following equation. That line is my flimsy attempt at making it a fraction..

\(\displaystyle \displaystyle{\dfrac{3 * \frac{27}{12} + 2^4}{2 * 3^3 - 2 * \sqrt{25}}}\)

I followed PEMDAS as best I could, and got the answer of 91/160... I think I am not doing it correctly.


What is PEMDAS? Never heard of it. Anyway, take caution on order of operations and maybe you should try doing separately the expression in denominator and then the expression in numerator. Maybe it would be less confusing that way for you. Also, as colleague said, you should show us how you came to that result; the whole process. In that case we would be able to point out the mistake that you've made in your arithmetic.
 
What is PEMDAS? Never heard of it. Anyway, take caution on order of operations and maybe you should try doing separately the expression in denominator and then the expression in numerator. Maybe it would be less confusing that way for you. Also, as colleague said, you should show us how you came to that result; the whole process. In that case we would be able to point out the mistake that you've made in your arithmetic.
Parentheses, Exponents, Multiply or Divide, Add or Subtract

I agree. You can think of the long horizontal line as parentheses grouping the top and the bottom.
 
I need some assistance with answering the following equation.
An "equation" has an "equals" sign in it, and asks for the value of a variable (a letter) to be found in some manner. I will guess that the instructions actually said something more like "evaluate the expression"...?

\(\displaystyle \displaystyle{\dfrac{3 * \frac{27}{12} + 2^4}{2 * 3^3 - 2 * \sqrt{25}}}\)

I followed PEMDAS as best I could, and got the answer of 91/160... I think I am not doing it correctly.
Since we cannot see your work, there is no way to tell where errors cropped up. Please reply with this necessary information. Thank you! ;)
 
Hello,

Thank you for the prompt replies..! Sorry, yes it asks to evaluate the expression.. and there is an equal sign!

Okay, this is my answer if I evaluate the denominator FIRST.
2 x 3^3 - 2 ( square root of 25)
Becomes, 2 x 27 - 10 = 44

For the numerator, I get this.

3(27/12) + 2^4,

Becomes, 3 ( 2.25) + 16 = 22.75

Now I have to get rid of the decimal placing, so I go from 22.75/1 to 2275/100.

Now I have 2275/100 / 44/1

I originally came up with 91/160, by converting 44/1 to 4400/100 like I did with the numerator. Then I simplified them as much as possible.
 
Hi there,

I need some assistance with answering the following equation. That line is my flimsy attempt at making it a fraction..

\(\displaystyle \displaystyle{\dfrac{3 * \frac{27}{12} + 2^4}{2 * 3^3 - 2 * \sqrt{25}}}\)

I followed PEMDAS as best I could, and got the answer of 91/160... I think I am not doing it correctly.

\(\displaystyle \displaystyle{\dfrac{3 * \frac{27}{12} + 2^4}{2 * 3^3 - 2 * \sqrt{25}}}\)

\(\displaystyle = \ \displaystyle{\dfrac{\frac{27}{4} + 16}{2 * 27 - 2 * 5}}\)

\(\displaystyle = \ \displaystyle{\dfrac{\dfrac{91}{4}}{54 - 10}}\)

\(\displaystyle = \ \displaystyle{\dfrac{\frac{91}{4}}{44}}\)

\(\displaystyle = \ \displaystyle{\dfrac{91}{4} \ * \ \dfrac{1}{44}}\)

\(\displaystyle = \ \displaystyle{\dfrac{91}{4 * 44}}\)

\(\displaystyle = \ \displaystyle{\dfrac{91}{176}}\)
 
Hello,

Thank you for the prompt replies..! Sorry, yes it asks to evaluate the expression.. and there is an equal sign!

Okay, this is my answer if I evaluate the denominator FIRST.
2 x 3^3 - 2 ( square root of 25)
Becomes, 2 x 27 - 10 = 44

For the numerator, I get this.

3(27/12) + 2^4,

Becomes, 3 ( 2.25) + 16 = 22.75

Now I have to get rid of the decimal placing, so I go from 22.75/1 to 2275/100.

Now I have 2275/100 / 44/1

I originally came up with 91/160, by converting 44/1 to 4400/100 like I did with the numerator. Then I simplified them as much as possible.
To continue with what you have for a numerator
n = \(\displaystyle \frac{2275}{100}\)
and denominator
d = \(\displaystyle \frac{4400}{100}\)
Now we invert the denominator and multiply so that we have
\(\displaystyle \frac{n}{d}\, =\, \frac{2275}{100}\,\, *\,\, \frac{100}{4400}\, =\, \frac{2275}{4400}\)
= \(\displaystyle \dfrac{5^2*7*13}{2^4*5^2*11}\,\, =\,\, \dfrac{7*13}{2^4*11}\,\, =\,\, \dfrac{91}{176}\)

Although there is nothing wrong with your approach (as long as you don't make a mistake), I personally prefer the way Subhotosh Khan did it.
 
Although there is nothing wrong with your approach (as long as you don't make a mistake), I personally prefer the way Subhotosh Khan did it.

Yeah Denis.... Take that.....
 
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To learn how to type math as text, try here.

And, by the way, the original expression involved a fraction, which is division:

. . . . .\(\displaystyle \displaystyle{\dfrac{3 * \frac{27}{12} + 2^4}{2 * 3^3 - 2 * \sqrt{25}}}\)

So your working is not correct. Sorry. :oops:
 
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