Those are commonly used for working with fractions. You need the least common multiple to find a common denominator, for adding or subtracting fractions. And after doing some manipulations with fractions, you need the greatest common factor to simplify the fractions.
Now, whether this is sufficiently "real-life" for you, is another issue. Depending on the career you choose, you many need to work with fractions on a daily basis, or you may hardly ever need them.
In finding the LCM or HCF of two or more numbers
To add fractions.
The LCM of 6 and 15 is 30.
When adding or subtracting fractions with different denominators the LCD is found with the LCM.
The LCM of 3 and 6 is 6 The LCM of 5 and 7 is 35. The LCM of 8 and 9 is 72. The LCM of 12 and 15 is 60.
The LCM of 3 and 4 is 12. The LCM of 5 and 15 is 15. The LCM of 24 and 36 is 72. The LCM of 24 and 81 is 648.
For the division of quantities
7 can divide into the LCM of some sets of numbers, not others.
The LCM of 2 and 3 is 6. The LCM of 2 and 4 is 4. The LCM of 5 and 7 is 35. The LCM of 7 and 9 is 63.
In a non-academic, practical setting the LCM is used when unlike fractions are added or subtracted, like when a carpenter has to add measurements of eights and sixteenths.
Finding the LCM will help you add and subtract fractions. Finding the GCF will help you reduce fractions.
We use the LCM to find the least common denominator of unlike fractions.
You would use it when adding fractions.
Adding or subtracting fractions requires the use of a common multiple. It is rare that the LEAST common multiple is required - it is useful to keep the numbers small and manageable.
Example: 30 and 42 The GCF is 6. The LCM is 210.
Use the GCF to reduce fractions. Use the LCM to add and subtract unlike fractions. Carpenters work with fractions a lot.
The HCF helps in simplifying fractions and the LCM helps in finding the lowest common denominator in fractions
There are some schools of thought that maintain that a fraction can have an LCM. For our purposes, we find the LCM of the denominators to discover a least common denominator. The LCM of 9 and 15 is 45.
to measure the tiles for our floor, if you need larger tiles so you could find by HCF and if smaller tiles you could find that by LCM
LCM is used to find the lowest common denominator in fractions HCF is used to reduce fractions to their simplest terms
In order to have an LCM, there has to be two or more numbers. Some multiples of 30 are 60, 90, 120, etc.
Let us say you take Tylenol every 4 hours and Motrin every 6 hours. How often do you need to take both medications at once? To answer this, you need to find the LCM of 4 and 6 which is 12. So every 12 hours you take both drugs at the same time.