Multiple choice

Directions: Find the missing term in the following number series. 10, 14, 25, 55, 140, ?

  1. 386

  2. 398

  3. 388

  4. 396

  5. 376
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C Correct answer
Explanation

Series: 10, 14, 25, 55, 140. Differences: 4, 11, 30, 85. Second differences: 7, 19, 55. Pattern: 4*2+3=11, 11*2+8=30, 30*2+25=85. The next difference is 85*2 + 78 = 248. 140 + 248 = 388.

AI explanation

The differences between the terms are sequentially multiplied by prime numbers and added to the previous term. The initial differences are 4, 11, 30, and 85, which are products of multiplying the previous difference by increasing fractions. The next difference is calculated as 140 multiplied by 2 plus 108, giving 248. Adding 248 to 140 gives the final result of 388.

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