All Exams Test series for 1 year @ ₹349 only
Question

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

6, 6, 18, 90, 630, ?

This question was previously asked in
SSC Selection Post 2021 Question Paper (09-Feb-2022) (Shift-1)
The correct answer is

5670

Finding the Missing Number in the Series

The question asks us to identify the correct number to replace the question mark (?) in the given number series. The series provided is: 6, 6, 18, 90, 630, ?

Analyzing the Series Pattern

To find the missing number, we first need to understand the pattern governing the series. Let's examine the relationship between consecutive terms:

  • The first term is 6.
  • The second term is 6. The relationship between the first and second term is $6 \times 1 = 6$.
  • The third term is 18. The relationship between the second and third term is $6 \times 3 = 18$.
  • The fourth term is 90. The relationship between the third and fourth term is $18 \times 5 = 90$.
  • The fifth term is 630. The relationship between the fourth and fifth term is $90 \times 7 = 630$.

By observing these steps, we can see a clear pattern: each term is obtained by multiplying the previous term by consecutive odd numbers, starting from 1. The sequence of multipliers is 1, 3, 5, 7.

Calculating the Next Number

Following the established pattern, the next multiplier should be the next odd number after 7, which is 9.

To find the missing number (the sixth term in the series), we need to multiply the last given term (630) by the next multiplier (9).

The calculation is as follows:

$$630 \times 9$$

Let's perform the multiplication:

$$630 \times 9 = 5670$$

So, the number that should replace the question mark is 5670.

Selecting the Correct Option

We need to choose the option that matches our calculated value.

  • Option 1: 8500
  • Option 2: 1260
  • Option 3: 4250
  • Option 4: 5670
  • Option 5: (No value provided)

Our calculated result is 5670, which corresponds to Option 4.

Was this answer helpful?

Similar Questions

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

    6, 8, 11, 16, ?, 34, 47, 64

  2. Which number will replace the question mark (?) in the following series?

    36, 512, 100, 1728, ?, 4096

  3. Which number will replace the question mark (?) in the following series?

    11, 19, ?, 49, 79, 128

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

    16, 18, 24, 36, ?, 86

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

    304, 261, 221, 184, ?, 119

  6. Select the option that represents the letters which when sequentially placed from left to right in the blanks below will complete the letter series.

    P _ I _ Y _ O _ U Y P _ K U _ P O _ _ Y

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

    98, 97, 101, 92, ?

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

    8, 15, 25, 38, ?, 73

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

    7, 7, 5, 15, 11, 55, 49, 343, ?

  10. Which number will replace the question mark (?) in the following series?

    11, 30, 68, 144, 296, ?


Important Questions from Number Series

  1. What will come in place of question mark (?) in the following number series?

    2, 5, 11, 23, 44, 77, ?

  2. What will come in place of question mark (?) in the following number series?

    31, 32, 36, ?, 61, 86

  3. What will come in the place of question mark (?) in the following number series?

    3, 6, 18, ?, 630, 6930

  4. What should come in place of the question mark ‘?’ in the following number series?

    60, 40, 50, ?, 180, 460

  5. A series is given with one term wrong. Select that wrong term from the given alternatives.

    J12, M24, P48, S96, U192

Need Expert Advice?
Upcoming Exams
SSC JHT
September 13, 2026
SSC Selection Post
September 16, 2026
SSC CGL
September 30, 2026
UPSSSC PET
October 23, 2026
Test Series
SSC Selection Post img
SSC
SSC Selection Post (Graduation) (Phase 12) 2025 Mock Test Series
489 Tests 5 Tests Free
5425 Attempts
4.8(312)
English, Hindi

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App