Number series (identify the missing square): Odd-number squares sequence. Given sequence: 1, 9, 25, 49, ?, 121 Fill the missing perfect square of an odd integer. Choose the correct value.

Q: Number series (identify the missing square): Odd-number squares sequence. Given sequence: 1, 9, 25, 49, ?, 121 Fill the missing perfect square of an odd integer. Choose the correct value.

Observation Sequence = 1², 3², 5², 7², 9², 11², ... Missing term After 7² = 49, the next is 9² = 81, then 11² = 121.

Difficulty: Easy

64
81
91
100

Correct Answer: 81

Explanation:

Observation
Sequence = 1², 3², 5², 7², 9², 11², ...

Missing term
After 7² = 49, the next is 9² = 81, then 11² = 121.

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