Question

Find the smallest number that is divisible by all even numbers 5 and 15 is ?

Answer 1

You need to find LCM of all even number between 5 and 15

even number between 5 and 15 are - 6 , 8 , 10 , 12 , 14

LCM (6,8,10,12) is

6 = 2× 3
8 = 2^3
10 = 2×5
12 = 3×2^2
14 = 7 × 2

Then , LCM = 2^3 × 5 × 3 ×7
= 840

840 is Required Number