one step addition equation help.

bobisaka

Junior Member
Joined
Dec 25, 2019
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115
In step 3, how did the fractions come to multiplying with those particular numbers?



math.pngone step addi
 
You can multiply any number by 1 and not change its value. Now there are many many ways to write 1, like 7/7, -9/-9, .456/.456, etc.
The two fractions have the denominators as 6 and 9.
Write out the (or think of) times take for 6 and 9 and look for the FIRST common factor. The answer is 18.
Now how do you go from 6 to 18? You multiply by 3, so you multiply (11/6) by (3/3).
Same idea for other fraction.

You CAN NOT add fractions until the denominators are the same!
 
I think you have doubt about why 11/6 is multiplied by 3 & 7/9 is multiplied by 2..
If i am correct, then let me explain in a simple language-
When you have to add or subtract 2 fractions, then first you should make their denominator same.
In this case, denominators are 6 & 9. To make them equal, we can multilply first fraction by 3 in numerator as well as in denominator. Similarly multiply second fraction by 2 in numerator as well as denominator.
After this we get 18 as common denominator of both the fractions, now you can subtract numerators keeping denominator as 18.
So you got answer as 19/18.
 
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