Multiple choice

Directions: Find the wrong term in the following series. 361, 529, 841, 961, 1369, 1521

  1. 1521

  2. 1369

  3. 961

  4. 841

  5. 529
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The series consists of squares of prime numbers: 19^2=361, 23^2=529, 29^2=841, 31^2=961, 37^2=1369. The next prime after 37 is 41, and 41^2 = 1681. The term 1521 is 39^2, which is not a prime square.

AI explanation

All the given numbers except 1521 are perfect squares of consecutive prime numbers. The sequence of bases is 19 squared for 361, 23 squared for 529, 29 squared for 841, 31 squared for 961, and 37 squared for 1369. The number 1521 is 39 squared, but 39 is a composite number and not a prime, making it the wrong term in the series.

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