Answer:
the product of the two numbers
Explanation:
The LCM of two numbers is their product, divided by their GCF. If their GCF is 1, then the LCM will be their product. That is the most it can be.
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We assume you're concerned with whole numbers. For rational numbers, the GCF may be a fraction, so the LCM may be larger than the product of the numbers.
LCM(5, 6) = 5·6/GCF(5, 6) = 5·6/1 = 30
LCM(1/2, 3/4) = (1/2)(3/4)/GCF(1/2, 3/4) = (3/8)/(1/4) = 3/2