Find the sum of all natural numbers lying between 100 and 1000, which are multiples of 5.

Explanation

To find the sum of all natural numbers lying between 100 and 1000 that are multiples of 5, we can follow these steps:

### Step 1: Identify the first and last terms
The first multiple of 5 greater than 100 is 105, and the last multiple of 5 less than 1000 is 995.

### Step 2: Write the series
The series of multiples of 5 between 100 and 1000 can be written as:
\[ 105, 110, 115, \ldots, 995 \]
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