To find the LCD (least common denominator) of a number, all we have to do is list the multiples of each of them and then pinpoint the lowest match.
For 1/4 : 4, 8, 12, 16, 24, 28
For 2/3 : 3, 6, 9, 12, 15, 18
As you can see, I've bolded the LCD in these number sets. 12 is the LCD of these two fractions because it is the lowest multiple of each denominator that matches up.
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