Find the LCM of all the numbers from 1 to 10 (both inclusive)
there are 10 numbers including 1 and 10
1 2 3 4 5 6 7 8 9 10
all numbers are divisible by 1
numbers divisible by 8 are also divisible by 2 and 4
numbers divisible by 9 are also divisible by 3 and 6
number 10 is dividible by 5 and 2
so, eliminate the common factors
so, 5 7 8 and 9 are the unique ones
so, 5*7*8*9=2520