Question

Find out the wrong number in the sequence:
25, 36, 49, 81, 121, 169, 225

• A. 36
• B. 49
• C. 121
• D. 169

Hint:

All other numbers are squares of consecutive odd numbers ($5^2, 7^2, 9^2, 11^2, 13^2, 15^2$). 36 is $6^2$ (even).

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Analyzing the mathematical property and base number parity of the perfect squares in the series.

Step 2: Key Formula or Approach:
The sequence comprises squares of consecutive odd integers:
\[5^2 = 25\] \[7^2 = 49\] \[9^2 = 81\] \[11^2 = 121\] \[13^2 = 169\] \[15^2 = 225\]

Step 3: Detailed Explanation:
The number 36 is $6^2$, which is the square of an even number and does not belong to the sequence of odd squares.

Step 4: Final Answer:
Hence, the wrong number in the sequence is 36.