Multiple choice

DIRECTION for the question: find wrong number of series 789, 645, 545, 481, 440, 429, 425

  1. 645

  2. 545

  3. 481

  4. 440

  5. 429
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D Correct answer
Explanation

The differences between consecutive terms in the series are consecutive decreasing even squares: 12^2, 10^2, 8^2, 6^2, 4^2, and 2^2. Subtracting 8^2 (64) from 545 gives 481, and subtracting 6^2 (36) from 481 should give 445 instead of 440.

AI explanation

The pattern in the series subtracts the cubes of consecutive integers starting from 3. The correct sequence should be 789 - 3 cubed (27) = 762, 762 - 4 cubed (64) = 698, 698 - 5 cubed (125) = 573, 573 - 6 cubed (216) = 357, and 357 - 7 cubed (343) = 14. Since the series lists 645, 545, 481, 440, 429, and 425, the correct calculation does not match the provided numbers. The wrong number in the series is 440.

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