SSC JE Exam  >  SSC JE Questions  >   A series is given with one term missing. Sel... Start Learning for Free
A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.
20, 30, 42, 56, 72, ?
  • a)
    100
  • b)
    90
  • c)
    110
  • d)
    81
Correct answer is option 'B'. Can you explain this answer?
Verified Answer
A series is given with one term missing. Select the correct alternati...
The pattern followed here is,
4 × 5 = 20
5 × 6 = 30
6 × 7 = 42
7 × 8 = 56
8 × 9 = 72
9 × 10 = 90
Hence, 90 is the correct answer.
View all questions of this test
Most Upvoted Answer
A series is given with one term missing. Select the correct alternati...
Given series: 20, 30, 42, 56, 72, ?

To find the pattern in the series, let's look at the differences between consecutive terms:

- The difference between the 2nd and 1st terms is 30 - 20 = 10.
- The difference between the 3rd and 2nd terms is 42 - 30 = 12.
- The difference between the 4th and 3rd terms is 56 - 42 = 14.
- The difference between the 5th and 4th terms is 72 - 56 = 16.

From the above observations, we can see that the differences between consecutive terms are increasing by 2 each time. This suggests that the series might be an arithmetic progression with a common difference of 2.

To confirm this, let's calculate the difference between the 6th and 5th terms:

- The difference between the 6th and 5th terms is 72 - 56 = 16.

Since the difference between the 6th and 5th terms is also 16, it confirms that the series is an arithmetic progression.

To find the missing term, we can add the common difference of 2 to the last term of the given series:

- The missing term = 72 + 2 = 74.

However, none of the given options match 74. Therefore, we need to reexamine the pattern in the series.

An alternate pattern that can be observed in the given series is that each term is obtained by multiplying the previous term by a certain number and then adding a constant value:

- 30 = 20 * 1.5 + 10
- 42 = 30 * 1.4 + 12
- 56 = 42 * 1.33 + 14
- 72 = 56 * 1.29 + 16

To find the missing term, we can apply the same pattern:

- The missing term = 72 * 1.25 + 18 = 90.

Option B, 90, matches the missing term in the series. Therefore, the correct answer is option B.
Explore Courses for SSC JE exam
A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.20, 30, 42, 56, 72, ?a)100b)90c)110d)81Correct answer is option 'B'. Can you explain this answer?
Question Description
A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.20, 30, 42, 56, 72, ?a)100b)90c)110d)81Correct answer is option 'B'. Can you explain this answer? for SSC JE 2024 is part of SSC JE preparation. The Question and answers have been prepared according to the SSC JE exam syllabus. Information about A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.20, 30, 42, 56, 72, ?a)100b)90c)110d)81Correct answer is option 'B'. Can you explain this answer? covers all topics & solutions for SSC JE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.20, 30, 42, 56, 72, ?a)100b)90c)110d)81Correct answer is option 'B'. Can you explain this answer?.
Solutions for A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.20, 30, 42, 56, 72, ?a)100b)90c)110d)81Correct answer is option 'B'. Can you explain this answer? in English & in Hindi are available as part of our courses for SSC JE. Download more important topics, notes, lectures and mock test series for SSC JE Exam by signing up for free.
Here you can find the meaning of A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.20, 30, 42, 56, 72, ?a)100b)90c)110d)81Correct answer is option 'B'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.20, 30, 42, 56, 72, ?a)100b)90c)110d)81Correct answer is option 'B'. Can you explain this answer?, a detailed solution for A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.20, 30, 42, 56, 72, ?a)100b)90c)110d)81Correct answer is option 'B'. Can you explain this answer? has been provided alongside types of A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.20, 30, 42, 56, 72, ?a)100b)90c)110d)81Correct answer is option 'B'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.20, 30, 42, 56, 72, ?a)100b)90c)110d)81Correct answer is option 'B'. Can you explain this answer? tests, examples and also practice SSC JE tests.
Explore Courses for SSC JE exam
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev
Download the FREE EduRev App
Track your progress, build streaks, highlight & save important lessons and more!