Solve any three sub questions from the following :
Find the LCM of 20 and 15.

Explanation

To find the Least Common Multiple (LCM) of 20 and 15, we can use the long division method. Here’s a step-by-step solution:

### Step 1: Write the numbers
We start with the two numbers we want to find the LCM for: 20 and 15.

### Step 2: Divide by the smallest prime number
We will divide both numbers by the smallest prime number that can divide at least one of them. The smallest prime number is 2.

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