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Question

Complete the series :
7, 14, 11, 22, 17, 34, ?

The correct answer is
27

Solving the Number Series: 7, 14, 11, 22, 17, 34, ?

To complete the given number series, we need to identify the underlying pattern or logic connecting the numbers. Let's examine the relationship between consecutive terms:

  • The first term is 7.
  • The second term is 14. The operation from 7 to 14 is multiplication by 2: 
    \(7 \times 2 = 14\)
  • The third term is 11. The operation from 14 to 11 is subtraction of 3: 
    \(14 - 3 = 11\)
  • The fourth term is 22. The operation from 11 to 22 is multiplication by 2: 
    \(11 \times 2 = 22\)
  • The fifth term is 17. The operation from 22 to 17 is subtraction of 5: 
    \(22 - 5 = 17\)
  • The sixth term is 34. The operation from 17 to 34 is multiplication by 2: 
    \(17 \times 2 = 34\)

Identifying the Pattern

The series follows an alternating pattern of two operations:

  1. Multiplying the current number by 2.
  2. Subtracting a number from the current number.

Let's look at the numbers being subtracted: 3, 5. This sequence consists of consecutive odd numbers, increasing by 2 each time.

Determining the Next Term

Following the established pattern:

  • The last operation was multiplication by 2 (17 * 2 = 34).
  • The next operation should be subtraction.
  • The sequence of subtractions is 3, 5. The next odd number in this sequence is 7 (since 5 + 2 = 7).
  • Therefore, we subtract 7 from the last term (34): 
    \(34 - 7 = 27\)

Thus, the next number in the series is 27.

Final Answer Verification

The series progresses as follows:

  • 7
  • \(7 \times 2 = 14\)
  • \(14 - 3 = 11\)
  • \(11 \times 2 = 22\)
  • \(22 - 5 = 17\)
  • \(17 \times 2 = 34\)
  • \(34 - 7 = 27\)

The number 27 correctly follows the identified pattern.

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Important Questions from Series (Notes)

  1. Which one of the following images numbered as (1), (2), (3), (4) will be the next image for the given series?

  2. What will be written in the place of question mark  in the given series? 

    M13J10N14R18?9

  3. Which one of the following images numbered as (1), (2), (3), (4) will be the next image for the given series?

  4. What will be written in the place of question mark in the given series? 

    Y25M13Q17D4?12

  5. Which one of the following images numbered as (1), (2), (3), (4) will be the next image for the given series?

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