How do you solve x/2 + 2/3 = 5/6?

2 Answers
May 23, 2016

x = 1/3

Explanation:

x/2 + 2/3 =5/6

x/2 =5/6 - 2/3

The L.C.M of the denominators of the fractions of the R.H.S = 6

x/2 =5/6 - (2 *2) / (3 *2)

x/2 =5/6 - 4/6

x/2 =1/6

x =(1/6) *2

x = 1/3

May 23, 2016

Alternative approach

x=1/3

Explanation:

Notice that all the denominators are factors of 6

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To change the way a number looks without changing its value multiply by 1 but where 1 is in another form. For example

Changing x/2 into 6 "th"^("s") multiply by 1 but in the form of 1=3/3" "-> x/2xx3/3=(x xx3)/(2xx3) = (3x)/6

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Given:" "x/2+2/3=5/6

Write as:" " (x/2xx3/3)+(2/3xx2/2)=5/6

=> (3x)/6+4/6=5/6

As everything is divided by 6 the equation is also true if we totally ignored the 6. Alternatively if you are not 'happy' about doing that this will get you to the same point:

Multiply everything by 6 giving:

3x+4=5

Subtract 4 from both sides:

3x=1

Divide both sides by 3

x=1/3