Number series – find the wrong term (identify the outlier). Sequence: 56, 72, 90, 110, 132, 150

Difficulty: Easy

Correct Answer: 150

Explanation:

Introduction / Context:This is a difference-pattern series where each step increases by a steadily growing even number. One term breaks the pattern and must be identified.

Given Data / Assumptions:

  • Series: 56, 72, 90, 110, 132, 150
  • One term is incorrect.

Concept / Approach:Compute successive differences and check whether they follow a simple progression, such as adding even numbers that increase by 2 each time.

Step-by-Step Solution:

72 − 56 = 1690 − 72 = 18110 − 90 = 20132 − 110 = 22Expected next difference is 24, so expected next term = 132 + 24 = 156.Given final term is 150, which is short by 6 and breaks the +2-increment pattern of the differences.

Verification / Alternative check:Replace 150 with 156 to obtain differences 16, 18, 20, 22, 24, a consistent arithmetic progression of even numbers.

Why Other Options Are Wrong:

  • 72, 110, 132: Each fits perfectly into the growing-difference pattern.

Common Pitfalls:Looking at ratios when the structure is additive. Always test both methods, but here differences immediately reveal the rule.

Final Answer:150

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