what is the difference between the least common multiple and the least common denominator?

Question

owlfred · Answer

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anonymous · Answer

nothing except that "least common denominator" refers to the least common multiple of the denominator

jocelyn · Answer

LCM is the smallest unit that two numbers can go into, for example:
Multiples of 5 are: 5, 10, 15, 20, 25
Multiples of 4 are: 4, 8, 12, 16, 20, 24
The smallest unit that both of these have in common is 20, so 20 is the LCM.

LCD is the smallest unit that two fractions have in common, for example:
1/3 and 1/5. The same rule applies as LCM
Multiples of 3: 3, 6, 9, 12, 15, 18
Multiples of 5: 5, 10, 15, 20, 25

15 is the common denominator, so 1/3 and 1/5 would both equal to 5/15 and 3/15. 15 is the LCD

The only difference is LCM deals with whole numbers and LCD deals with fractions of a whole number.