Multiple choice

The wrong (misfit) number of the sequence 4, 9, 25, 49, 121, 144 is

  1. 21

  2. 49

  3. 144

  4. 9
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C Correct answer
Explanation

The numbers 4, 9, 25, 49, and 121 are squares of consecutive primes: 2^2, 3^2, 5^2, 7^2, and 11^2. The next term should be 13^2 = 169, so 144 is the misfit.

AI explanation

The sequence consists of squares of consecutive prime numbers: 2 squared is 4, 3 squared is 9, 5 squared is 25, and 7 squared is 49. Since 144 is the square of 12, which is not a prime number, it is the misfit in the sequence.

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