Question:
Find the missing number in the series: 3, 7, 13, 21, 31, ___
Find the missing number in the series: 3, 7, 13, 21, 31, ___
Show Hint
When differences increase steadily, the sequence is based on an arithmetic progression of differences.
Updated On: Jun 26, 2026
- 43
- 53
- 41
- 55
Show Solution
Verified By Collegedunia
The Correct Option is A
Solution and Explanation
Step 1: Concept
Finding the pattern in a numerical series.
Step 2: Analysis
Calculate the differences between terms: - $7 - 3 = 4$ - $13 - 7 = 6$ - $21 - 13 = 8$ - $31 - 21 = 10$
Step 3: Calculation
The differences are increasing by 2 each time (4, 6, 8, 10). The next difference should be $10 + 2 = 12$. Missing number = $31 + 12 = 43$.
Step 4: Conclusion
Correct missing number is 43. Final Answer: (1)
Finding the pattern in a numerical series.
Step 2: Analysis
Calculate the differences between terms: - $7 - 3 = 4$ - $13 - 7 = 6$ - $21 - 13 = 8$ - $31 - 21 = 10$
Step 3: Calculation
The differences are increasing by 2 each time (4, 6, 8, 10). The next difference should be $10 + 2 = 12$. Missing number = $31 + 12 = 43$.
Step 4: Conclusion
Correct missing number is 43. Final Answer: (1)
Was this answer helpful?
0
0
Top APICET Analytical Ability Questions
- In which year was Rahul born?
I) Rahul is 25 years younger to his mother.
II) Rahul's brother, who was born in 1964, is 35 years younger to his mother. - Who among P, Q, T, V and M is exactly in the middle when they are arranged in ascending order of their heights?
I) V is taller than Q but shorter than M.
II) T is taller than Q and M but shorter than P. - The last Sunday of March 2006 fell on which date?
I) The first Sunday of that month fell on 5th.
II) The last day of month was not Saturday. - Which code word stands for ‘good’ in the coded sentence ‘sin co bye’ which means ‘He is good’?
I) In the same code language, ‘co mot det’ means ‘They are good’.
II) In the same code language, ‘sin mic bye’ means ‘He is honest’. - What is the buying cost of the shirt? Statements:
I) The shirt was sold for Rs.800 at a 20% profit.
II) The difference between the selling price and the cost price is Rs.160.
View More Questions
Top APICET Sequences and Series Questions
- Which of the following is an arithmetic sequence?
- Find the \( 15^{\text{th}} \) term of the Fibonacci series if the \( 13^{\text{th}} \) and \( 14^{\text{th}} \) terms are 144 and 233 respectively.
If the 1st term of a G.P. is 2 and the 3rd term is 8, find the common ratio.
- What is the sum of the following series?
\[ -64,\ -66,\ -68,\ ......,\ -100 \] - Find the odd one out from the following series:
\[ 8,\ 27,\ 64,\ 100,\ 125,\ 216,\ 343 \]
View More Questions