Watch Video on Lowest Common Denominator - Pre Algebra Help
Thursday, September 10th, 2009
Access full lesson containing this video at: http://www.yourteacher.com/prealgebra/leastcommondenominator.php Students learn to add unlike fractions by first finding a common denominator. For example, to add 1/2 + 1/3, first find the common denominator of 2 and 3, or the Least Common Multiple of 2 and 3, which is 6. Then multiply the numerator and denominator of 1/2 by 3, to get the equivalent fraction 3/6, and multiply the numerator and denominator of 1/3 by 2, to get the equivalent fraction 2/6. Next, add the like fractions, 3/6 + 2/6, to get 5/6. So 1/2 + 1/3 = 5/6. Students also learn to subtract unlike fractions by following the same process that is used when adding unlike fractions.
Duration : 0:1:18
Access full lesson containing this video at: http://www.yourteacher.com/algebra1/addingfractions.php Students learn to add or subtract fractions using the least common denominator, which is the least common multiple for the denominators of the fractions. Once the fractions are given a common denominator by multiplying the numerator and denominator of each fraction by the appropriate number, then the fractions can be added or subtracted by adding or subtracting the numerators, and leaving the denominator the same.