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Question

What is the sum of the first 25 odd numbers?

This question was previously asked in
RRB NTPC 2019 CBT 1 Question Paper PDF (31-Jan-2021) (Shift 1)
The correct answer is
625

The problem asks for the sum of the first 25 odd numbers.

Sum of First 25 Odd Numbers Calculation

There is a well-known formula for the sum of the first N odd positive integers. The sum is equal to N squared ($N^2$).

Applying the Formula

In this question, we need to find the sum of the first 25 odd numbers. This means our value for N is 25.

  • Identify N: \( N = 25 \)
  • Use the formula: Sum $= N^2$
  • Substitute the value of N: Sum $= 25^2$
  • Calculate the result: Sum $= 25 \times 25 = 625$

Therefore, the sum of the first 25 odd numbers is 625.

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