240=2x2x2x2x3x5
To find the LCm of 12, 16 and 20 you first need to break these numbers into their prime factors: 12 = 2x2x3 16 = 2x2x2x2 20 = 2x2x5 The next step is to identify any common factors. In this case, all three numbers have two 2s as prime factors, so we can discard 4 of them. Take every other prime factor (2, 2, 2, 2, 3 and 5) and multiply them together to find the LCM: 2x2x2x2x3x5 = 240 Thus the LCM of 12, 16 and 20 is 240.