Find the number that breaks the pattern: 2, 5, 10, 17, 28, 40, 58

Question

Find the number that breaks the pattern: 2, 5, 10, 17, 28, 40, 58

1. A. 10
2. B. 17
3. C. 40 (Correct answer)
4. D. 28

Correct Answer

Option C — 40

Detailed Solution & Explanation

The correct answer is 40.

Key Points

• Take the differences: 5 − 2 = 3, 10 − 5 = 5, 17 − 10 = 7, then 28 − 17 = 11, 40 − 28 = 12, 58 − 40 = 18.
• The first four differences are the primes 3, 5, 7, 11 — so the sequence should continue with 13 and 17.
• That gives 2, 5, 10, 17, 28, 41, 58. The listed 40 is the term that breaks the pattern.

Additional Information

• Confirming against the *last* term is what settles it: 41 + 17 = 58 matches the given final value, while 40 + 18 = 58 requires a difference that is not prime.
• Prime differences are a standard SSC construction; check 2, 3, 5, 7, 11, 13, 17 against the gaps whenever they look almost-but-not-quite arithmetic.
• When one term is wrong, verify the pattern on the terms after the suspect one too — a rule that only fits the start is not the rule.

प्रश्न (हिन्दी में)

वह संख्या ज्ञात कीजिए जो पैटर्न को तोड़ती है: 2, 5, 10, 17, 28, 40, 58

1. A. 10
2. B. 17
3. C. 40
4. D. 28