To find common denominators
you may take each denominator and provide the acceptable factors.
factors of 3: 1 , 3 , 6 , 9 , 12....ETC
factors of 4: 1 , 2 , 4 , 8 , 12...ETC
Note that they both have a common number of 12
So you will multiply the 1st fraction by 4 and the 2nd by 3
4(1/3) = 4/12
3(1/4) = 3/12
no need for the last part unless if you are proceeding with different properties.
