Sign Up FREE!  Sign In  Classroom Setup  Common Core Alignment  
05072014  #1 
Join Date: Jan 2012
Posts: 1

adding fractions with different denominators
I am preparing to take my GED at 51yrs old and I am a beginning learner of fractions. I am having difficulty finding the formula that will help me learn how to add and reduce these kind of fraction please help.

06012014  #2  
Join Date: Jun 2014
Posts: 1

Re: Adding Fractions with different denominators
Quote:
The LCM is determined by factoring both denominators into the factors If this sounds, lets try a simple example e.g. Lets add One and Twothirds plus 2 and Three Quarters (you'll note that the denominators 3, and 4, are different) 1 2/3 + 2 3/4 First, you'll need to convert both fractions into vulgar (improper) fractions. Do this by multiplying through the whole numbers by their denominators: (3 x 1 + 2) + (4 x 2 + 3) 3 4 = 5 + 11 3 4 Next up is to determine the Least Common Multiple. 3 is a prime number (3 x 1), and 4 has factors (1 x 4 and 2 x 2). There are no common factors of 3 and 4, so the Least Common Multiple is thus simply 3 x 4 = 12 So if we restate the addition of our 2 fractions with the LCM of 12: 5 + 11 3 4 = 4 x 5 + 11 x 3 12 (Since we need to multiply the left fraction by 4/4 and the right fraction by 3/3 to get to a common denominator of 12) = 20 + 33 12 = 53 12 The final step is to convert our answer back into a proper fraction. This is done by dividing the numerator by the 4 5 12 Which is the final answer! You can check your workings with this, and similar fractions at this website here: http://statsfiddle.info/Calculator/F...w2=2&n2=3&d2=4 

Thread Tools  
Display Modes  

