Question: why lcm is used in real life?
Answer: Originally Answered: When might you use the HCF and LCM in real life? The LCM is important when adding fractions which have different denominators. For example you want to add 1/2 to 1/3. If you know that the LCM of 2 and 3 is in fact 6 then you can say that really 1/2 is 3/6 and that 1/3 is really 2/6.