Answer:
The HCF of two or more numbers is the highest common factor of the given numbers. It is found by multiplying the common prime factors of the given numbers.
To get the Least Common Multiple (LCM) of 1820 and 3510 we need to factor each value first and then we choose all the factors which appear in any column and multiply them:
1820: 2 2 5 7 13
3510: 2 3 3 3 5 13
LCM: 2 2 3 3 3 5 7 13
The Least Common Multiple (LCM) is: 2 x 2 x 3 x 3 x 3 x 5 x 7 x 13 = 49140