The smallest number that can be used as the denominator (bottom number) for the given fractions.
• Denominator: the bottom number of a fraction (such as the 2 in ½)
• Common Denominator: when the denominator is the same for all given fractions
• Least Common Denominator: the smallest possible common denominator
Example: the Least Common Denominator of 1/2 and 2/3
1/2 can also be written as 2/4, or 3/6, or 4/8, etc
2/3 can also be written as 4/6, or 6/9, or 8/12, etc
Looking at those lists we can see that 3/6 and 4/6 have the same denominator, and it is the smallest such denominator
So the Least Common Denominator of 1/2 and 2/3 is 6
It makes it easy to add and subtract fractions.
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