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Question

Which of the following numbers will replace the question mark (?) in the given series?

233, 237, 245, 257, 273, ?

The correct answer is

293

Finding the Pattern in Number Series

The question asks us to find the next number in the given series: 233, 237, 245, 257, 273, ?

To solve number series problems, we need to identify the pattern or rule that relates consecutive terms. Let's find the difference between each pair of consecutive numbers in this series.

  • Difference between the 2nd and 1st term: ${237 - 233 = 4}$
  • Difference between the 3rd and 2nd term: ${245 - 237 = 8}$
  • Difference between the 4th and 3rd term: ${257 - 245 = 12}$
  • Difference between the 5th and 4th term: ${273 - 257 = 16}$

The differences we found are 4, 8, 12, 16. Let's examine this sequence of differences to find its pattern.

  • The difference between the 2nd and 1st difference is ${8 - 4 = 4}$.
  • The difference between the 3rd and 2nd difference is ${12 - 8 = 4}$.
  • The difference between the 4th and 3rd difference is ${16 - 12 = 4}$.

It appears that the differences between consecutive terms are increasing by a constant value of 4. This means the series has a pattern where the increment itself follows an arithmetic progression (4, 8, 12, 16, ...).

Following this pattern, the next difference in the sequence of differences (4, 8, 12, 16) should be the previous difference (16) plus 4. So, the next difference will be ${16 + 4 = 20}$.

Now, to find the next term in the original series, we add this next difference (20) to the last term in the series (273).

Next term = Last term + Next difference

Next term = ${273 + 20 = 293}$.

Therefore, the number that replaces the question mark (?) in the series is 293.

Let's verify the series with the differences:

  • 233 (+4) → 237
  • 237 (+8) → 245
  • 245 (+12) → 257
  • 257 (+16) → 273
  • 273 (+20) → 293

The pattern holds true.

Revision Table: Number Series Pattern Analysis

Term Number Term Value Difference from Previous Term
1 233 -
2 237 ${237 - 233 = 4}$
3 245 ${245 - 237 = 8}$
4 257 ${257 - 245 = 12}$
5 273 ${273 - 257 = 16}$
6 293 ${293 - 273 = 20}$

Additional Information: Types of Number Series Patterns

Number series questions can involve various types of patterns. Understanding common patterns can help solve these problems quickly.

  • Arithmetic Series: The difference between consecutive terms is constant (e.g., 2, 5, 8, 11... difference is 3).
  • Geometric Series: Each term after the first is found by multiplying the previous one by a fixed, non-zero number called the common ratio (e.g., 2, 6, 18, 54... common ratio is 3).
  • Series with Differences in AP: Like the series in this question, the differences between consecutive terms form an arithmetic progression (e.g., differences 4, 8, 12, 16...).
  • Series with Differences in GP: The differences between consecutive terms form a geometric progression (e.g., differences 2, 4, 8, 16...).
  • Fibonacci Series: Each term is the sum of the two preceding terms (e.g., 0, 1, 1, 2, 3, 5, 8...).
  • Prime Number Series: The terms are consecutive prime numbers (e.g., 2, 3, 5, 7, 11...).
  • Square or Cube Series: Terms are squares or cubes of natural numbers, or variations involving squares/cubes.
  • Mixed Series: A combination of two or more different patterns in alternate terms or a complex rule.

To solve a number series problem, always start by calculating the differences between consecutive terms. If the first differences don't show a clear pattern, calculate the differences of the differences (second differences) and so on. Sometimes, looking at ratios or other relationships between terms is necessary.

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Important Questions from Number Series

  1. Select the number from among the given options that can replace the question mark (?) in the following series.

    37, 52, 74, 104, 143, ?

  2. Select the number that can replace the question mark (?) in the following series.

    17, 19, 22, 27, 34, 45, 58,?
  3. Select the number from among the given options that can replace the question mark (?) in the following series.

    10, 14, 31, 35, 73, 77, ?

  4. Select the number from among the given options that can replace the question mark (?) in the following series.

    215, 231, 256, 292, ?

  5. Select the number from among the given options that can replace the question mark (?) in the following series.

    6, 6, 8, 24, 28, 140, ?

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