Select the number from among the given options that can…

Question

Select the number from among the given options that can replace the question mark (?) in the following series.
$23, 27, 43, 79, 143, ?$

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Question (English)

Select the number from among the given options that can replace the question mark (?) in the following series.
$23, 27, 43, 79, 143, ?$

  1. 240
  2. 243
  3. 200
  4. 250
Explanation:

Pattern Identification:

Calculate the difference between consecutive terms in the series:

  • $27 - 23 = 4$
  • $43 - 27 = 16$
  • $79 - 43 = 36$
  • $143 - 79 = 64$

Now, observe the pattern in the differences ($4, 16, 36, 64$):

  • $4 = 2^2$
  • $16 = 4^2$
  • $36 = 6^2$
  • $64 = 8^2$

The differences are squares of consecutive even numbers ($2, 4, 6, 8$). The next even number is $10$.

Next Step:
The next difference should be $10^2 = 100$.

Calculation:
$143 + 100 = 243$

Thus, the missing number is 243.

प्रश्न (हिंदी)

दिए गए विकल्पों में से उस संख्या का चयन करें जो निम्नलिखित श्रृंखला में प्रश्न चिह्न (?) को प्रतिस्थापित कर सकती है।
$23, 27, 43, 79, 143, ?$

  1. 240
  2. 243
  3. 200
  4. 250
स्पष्टीकरण:

पैटर्न की पहचान:

श्रृंखला के लगातार पदों के बीच का अंतर निकालें:

  • $27 - 23 = 4$
  • $43 - 27 = 16$
  • $79 - 43 = 36$
  • $143 - 79 = 64$

अब, अंतरों ($4, 16, 36, 64$) में पैटर्न देखें:

  • $4 = 2^2$
  • $16 = 4^2$
  • $36 = 6^2$
  • $64 = 8^2$

यहाँ अंतर लगातार सम संख्याओं ($2, 4, 6, 8$) के वर्ग हैं। अगली सम संख्या $10$ है।

अगला चरण:
अगला अंतर $10^2 = 100$ होना चाहिए।

गणना:
$143 + 100 = 243$

अतः, सही संख्या 243 है।

📚 About this Topic — General Awareness

This multiple choice question is from General Awareness, General Intelligence and Reasoning (2024), General Intelligence and Reasoning (2024)-2, SSC CGL Tier-1 (PYQs). It has 4 options with a detailed explanation of the correct answer and is available in both English and Hindi (द्विभाषी). Practice more MCQs from General Awareness to strengthen your preparation.

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