Take a lcm of 4,6,3,5,7,8,6,7,10?

Question

Take a lcm of 4,6,3,5,7,8,6,7,10?

Answer 1

Write each number in terms of its prime divisors, e.g. 4 = 2^2,

6 = 2 * 3, 8 = 2^3, 10 = 2*5, etc.

Look for the highest power of each prime: 2^3, 3, 5, 7.

Then the lcm is (2^3) * 3 * 5 * 7 = 8 * 3 * 5 * 7 = 840.

Answer 2

4 --> 2 x 2

6 --> 2 x 3

3 --> 3

5 --> 5

7 --> 7

8 --> 2 x 2 x 2

6 --> 2 x 3 (repeat)

7 --> 7 (repeat)

10 --> 2 x 5

Prime factors needed to cover all the cases:

2 x 2 x 2 x 3 x 5 x 7 = 840

Double check:

4 x 210 = 840

6 x 140 = 840

3 x 280 = 840

5 x 168 = 840

7 x 120 = 840

8 x 105 = 840

10 x 84 = 840

Answer:

LCM(4, 6, 3, 5, 7, 8, 6, 7, 10) = 840