Question

What is the LCM of 30 and 40?

Answer 1

Hint: In this problem, we have to find the Least common multiple of 30 and 40. Here we have found the least common multiple by listing the multiples method, which means the smallest number that two numbers both can get to or which is the common multiple between two numbers. We know that 30 and 40 has the smallest common factor which is the least common multiple. We can now find the number.

Complete step by step solution:
Here we have to find the least common multiple of 30 and 40.
We know that the least common multiple means the smallest number that two numbers both can get to or which is the common multiple between two numbers.
We can now write the multiple of 30,
\[\Rightarrow 30,60,90,120,150,180....\]
We can now write the multiple of 16, we get
\[\Rightarrow 40,80,120,160,200,240....\]
Here we can see that 120 is the smallest number which is common to the multiple of 30 and 40.
Therefore, the least common multiple of 30 and 40 is 120.

Note: We should remember the concept of least common multiple, which means the smallest number that two numbers both can get to or which is the common multiple between two numbers. We should know that we have different methods to find the least common multiple like listing the multiples, prime factorization and division method, here we have used listing the multiples method.