Add fractions using LCD
for 6th grade
Add fractions by finding the lowest common denominator (LCD); simplify your answers where possible
Adding fractions with different denominators
Add fractions using lowest common denominator (LCD)
Fractions with different denominators can be added by changing the fractions so that they share a common denominator.
Given the sum:
1/3 + 1/2
you do this by first finding the Lowest common multiple (LCM) of the denominators of both fractions.
The LCM is the smallest multiple shared by a set of numbers. For instance, some shared multiples of 2 and 3 are 6, 12 and 18, and the LCM is the smallest of those numbers which is 6. The LCM of 2 and 5 is 10 since 10 is the smallest multiple shared by 2 and 5.
Rewrite both fractions to use that LCM by multiplying both the numerator and the denominator by the same number. So, to convert 1/3 to have a denominator of 6, multiply both top and bottom by 2, giving 2/6.
Adding fractions with the same denominators
Once you have converted both fractions so that they share the same denominator, you can add the fractions by adding the numerators.
1/3 + 1/2 = 2/6 + 3/6 = 5/6
Below is a table showing the first 6 question answer pairs for the topic "Add fractions using LCD" as used in the lessons for this topic. Our games and tests for the topic use these 6 items plus 10 additional question answer pairs.
The topic "Add fractions using LCD" is in the category Number for 6th grade (ages 11 to 12).
Revise 'Add fractions using LCD' with one of our games for 6th grade
Each of our math topics for secondary are made up of between 6 and 20 question and answer pairs (both the written form and a robot voice speaking those questions and answers). Each topic can be used with all the activities on the site.
Number * Algebra * Ratio proportion rate * Geometry & measures * Probability * Statistics *
