Explanation:

- To find the LCM of two numbers, use the relation:

Product of numbers = LCM × HCF.

- Here, the product is given as 432 and HCF is 6.

- Use the formula: LCM = Product / HCF.

- Substitute the values: LCM = 432 / 6 = 72.

- Option 1: 68 is not the correct answer because it's not equal to 72.

- Option 2: 48 is not the correct answer as it doesn't match the calculated LCM.

- Option 3: 78 is incorrect since it doesn’t align with 72.

- Option 4: 72 is the correct answer, as it matches our calculation.

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