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hi I am new in maths and trying to practice it but I feel a lil lost in the one 3/4 +1/3 / 2/12 - 1/2=

 Mar 13, 2019
 #1
avatar+235 
+2

When you're adding or subtracting fractions, you always want to start by giving them all a common denominator. So, we have \(\frac {3/4 + 1/3}{2/12} - 1/2 = \frac {9/12 + 4/12}{2/12} - 6/12\). This helps us calculate the value without messing anything up. So adding the top part, we get \(\frac {13/12}{2/12} - 6/12\). The fraction on the bottom is pesky, so we flip 2/12 to 12/2, and now it's multiplying. \(13/12 \cdot 12/2 -6/12 = (13/2) \cdot 6 - 1/2\). 6 times 13 is 78, but we can't forget the denominator of two, so it turns out to be 39 - 1/2. The answer is 38 1/2. 

 

Hope this helps!

 Mar 13, 2019
 #4
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0

You did not follow the rule of GEMDAS. Division comes before any Addition or Subtraction.

 

\(\frac{3}{4}+\frac{1}{3}/\frac{2}{12}-\frac{1}{2}\). Following GEMDAS, you would do \(\frac{1}{3}/\frac{2}{12}\) first. Since, when dividing fractions, you really multiply them by the recipricol, you would really do \(\frac{1*12}{3*2}=\frac{12}{6}=2\).

 

Following the communitive property of addition, you would then do \(\frac{3}{4}+2-\frac{1}{2}=2+\frac{3}{4}-\frac{1}{2}\), to subtract the fractions easier.

 

NOW is when you find the common denominator, which is 4. You then get \(2+\frac{3}{4}-\frac{2}{4}=2+\frac{1}{4}=2\frac{1}{4}\).

 

So, \(2\frac{1}{4}\) is your final answer!

Guest Mar 13, 2019
edited by Guest  Mar 13, 2019
 #2
avatar+128475 
0

Need to be careful, here......assuming that we have

 

 3/4 +(1/3) /( 2/12) - 1/2 

 

We always perform any divisions from left to right before  any additions

 

So.....we really have

 

 3/4 +( [1/3] / [2/12] ) - 1/2 =

 

So.....we  are doing this, first :     (1/3 ) /  ( 2/12)   =    (1/3 ) / (1/6)  =  (1/3) * (6/1)  = 2

 

So....now we have

 

3/4 + 2 - 1/2  =

 

3/4 + 8/4 - 2/4  = 

 

11/4 - 2/4  =

 

9 / 4

 

 

cool cool cool

 Mar 13, 2019
 #3
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+1

According to GEMDAS, you do Division before Addition or Subtraction. I would split the problem into two seperate problems.

 

Since you start with division, start by doing \(\frac{1}{3}/\frac{2}{12}\). When dividing fractions, you take the dividend and multiply it by the reciprocal of the divisor, giving you \(\frac{1}{3}*\frac{12}{2}=\frac{12}{6}=2\).

So, now you have \(\frac{3}{4}+2-\frac{1}{2}=x\). Using the communitive property of addition, you can move the fractions closer together to make \(2+\frac{3}{4}-\frac{1}{2}=x\).

Now, you want a common denominator. The least common denominator is 4, so you can multiply \(\frac{1}{2}\) by 2 to get \(\frac{2}{4}\)

 

You should now have this: \(2+\frac{3}{4}-\frac{2}{4}\). Subtract the fractions first to get \(2+\frac{1}{4}\). Now, just add them together, to get \(2\frac{1}{4}\).

 

So, the final answer will be \(2\frac{1}{4}\)\(\frac{9}{4}\), or 2.25. Hope that this helped!

 Mar 13, 2019
edited by Guest  Mar 13, 2019

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