20 questions on “Logical Reasoning / Number Series Questions and Answers – III” series.
It is our effort to generate study material on this subject as this is being asked every now and then in government exams like bank PO, civil services etc.
Do let us know if you think anything needs to improved that can help you better in your exams.
Other Similar Articles:
Odd Man out: Part – I | Part II.
Table of Contents
Questions Section
Q1. Here is the number series to solve, if:
52 + 88 = 7280
20 + 46 = 1320
44 + 14 = 2552
91 + 3 = ? – what will be the number here?
Answer: 8554 i.e. 91 * (91 + 3)
52 * (52 + 88) = 7280,
20 * (20 + 46) = 1320, 44 * (44 + 14) = 2552
Logic: The logic is addition of both number multiplied by first number i.e.(52 + 88)*52=7280
Q2. Second question in the series is:
88 + 4 = 7392
60 + 75 = -900
92 + 82 = 920
55 + 54 = ? – what will be the number here?
Answer: 55 i.e. 55 * (55 – 54)
88 * (88 – 4) = 7392
60 * (60 – 75) = -900, 92 * (92 – 82) = 920
Logic: The logic is subtraction of both number multiplied by first number i.e.(88 – 4)*88=7392
Q3. Third question in the series is:
74 + 84 = 232
13 + 66 = 92
81 + 2 = 164
19 + 14 = ? – what will be the number here?
Answer: 52 i.e. 19*2 + 14
74*2 + 84 = 232
13*2 + 66 = 92, 81*2 + 2 = 164
Logic: The logic is 2 multiplied by first number plus second number i.e.(74*2 + 84)=232
Q4. What is the next number in the series:
38, 19.0, 9.5, 4.75, ?
Answer: 2.375 i.e. 4.75/2.
Logic: Second number is half of first one, 3rd number is half of second one and so on i.e. 38/2 =19.0, 19.0/2 =9.5, 9.5/2 =4.75 and so on.
Q5. Guess next number in the series:
44, 22.0, ??, 5.5, 2.75
Answer: 11.0 i.e. 22.0/2.
Logic: Second number is half of first one, 3rd number is half of second one and so on i.e.44/2 = 22.0, 22.0/2 = 11.0, 11.0/2 =5.5 and so on.
Q6. Guess next number in the series:
4, 16 , 64 , 256 , ?
Answer: 1024 i.e. 4^5
Logic: The series is square, cube, ^4 and so on i.e. 4*4 = 16 , 44*4 = 64 etc.
Q7. Guess next number in the series:
6, 36, ??, 1296, 7776
Answer: 216 i.e.6^3
Logic: The series is square, cube, ^4 and so on i.e. 6*6 = 36, , 66*6 = 216 etc.
Q8. Guess next number in the series:
9, 10, 12, 15, ?
Ans.19 i.e. 15 + 4
Second number is (1st number + 1), third number is (2nd number + 2), 4th is (3rd number + 3) and so on.
i.e. 9 + 1 = 10, 10 + 2 = 12, 12 + 3 = 15 and so on.
Q9. What will be the next number in the series:
7, 9, 13, 19, ?
Ans. 27 i.e. 12 + 8
Second number is (1st number + 2), third number is (2nd number + 4), 4th is (3rd number + 6) and so on.
7 + 2 = 9, 9 + 4 = 13, 13 + 6 = 19 and so on.
Q10. Find the missing number in the series:
0, 2, ??, 12, 20
Ans. 6 i.e. 2 + 4
0 + 2 = 2, 2 + 4 = 6, 6 + 6 = 12, 12 + 8 = 20,
Logic: Second number is (1st number + 2), third number is (2nd number + 4), 4th is (3rd number + 6) and so on.
Q11. Identify the missing number in the series:
28, 31, ??, 37, 40, 43
Ans. 34 i.e. 31 + 3
28 + 3 = 31, 31 + 3 = 34, 34 + 3 = 37, 37 + 3 = 40,
Logic: Second number is (1st number + 3), third number is (2nd number + 3), 4th is (3rd number + 3) and so on.i.e. every other number is previous number plus 3.
Q12. Identify the missing number in the series:
26, 29, ??, 38, 44, 51
Ans. 33 i.e. 29 + 4
26 + 3 = 29, 29 + 4 = 33, 33 + 5 = 38, 38 + 6 = 44, 44 + 7 = 51.
Logic: First number + 3 = 2nd number, second number + 4 = 3rd number, third number + 5 = 4th number and so on.
Q13. Find the missing number in the series:
26, 26, ??, 156, 624, 3120
Ans. 52 i.e. 26*2=52
26*1 = 26, 26*2 = 52, 52*3 = 156, 156*4 = 624, 624*5 = 3120.
Logic: First number*1 = 2nd number, second number*2 = 3rd number, third number*3 = 4th number and so on.
Q14. Find the missing number in the series:
24, 49, 73, ??, 121, 145
Ans. 97 i.e. (24*4 + 1)=97
24*2 + 1 = 49, 24*3 + 1 = 73, 24*4 + 1 = 97, 24*5 + 1 = 121, 24*6 + 1 = 145.
Logic: 1st number *2 + 1 = second, 1st number * 3 + 1 = third and so on.
Q15. Find the missing number in the series:
4, 10, 15, ??, 25, 30
Answer. 20 i.e.(4*4 + 4)=20
4*2 + 2 = 10, 4*3 + 3 = 15, 4*4 + 4 = 20, 4*5 + 5 = 25, 4*6 + 6 = 30.
Logic: 1st number *2 + 2 = second, 1st number * 3 + 3 = third, 1st number * 4 + 4 = fourth and so on.
Q16. A car crosses a 1720 m long road in 2 minutes. What will be it’s speed in km per hour?
Options:A. 17.028, B. 25.8, C. 30.96, D. 51.6
Answer: 51.6 km/h i.e. [(1720/1000) / (2/60)]
Logic: Converting 1720 to kilometer by dividing it by 1000 and converting 2 to hour by dividing it by 60 and dividing both.
Q17. Next number in the series is:
8, 11, 9, 12, 10, ??
Ans: 13 i.e. 10 + 3 = 13
8, 8 + 3 = 11, 11 – 2 =9 and so on i.e. +3 and then -2 in alternate numbers.
Logic: This is a simple alternating addition and subtraction series. In the first pattern, 3 is added; in the second, 2 is subtracted and so on.
Q18. Next number in the series is:
26, 24, 20, 18, 14, ??
Ans: 12 i.e. 14 – 2 = 12
26, 26 – 2 = 24, 24 – 4 =20 and so on i.e. -2 and then -4 in alternate numbers.
Logic: This is a simple alternating subtraction series. In the first pattern, 2 is subtracted; in the second, 4 is subtracted and so on.
Q19. Next number in the series is:
6, 5 , 7, 6, 8, ??
Ans: 7 i.e. 8 – 1 = 7
6, 6 – 1 = 5, 5 +2 =7 and so on i.e. -1 and then +2 in alternate numbers.
Logic: This is a simple alternating subtraction series. In the first pattern, 1 is subtracted; in the second, 2 is added and so on.
Q20. Next number in the series is:
38, 38, 27, 27, 16, ??
Ans: 16 i.e. 27 – 11 = 16
38, 38, 38 -11 = 27, 38 -11 = 27 and so on i.e. same number is repeated twice and then 11 is subtracted from it..
Logic: This is a simple alternating subtraction series. After repeating same number twice 11 is subtracted from it.
Conclusion
Please let us know if this article is of help or you want us to improve anything or want us to generate article on any other thing.
we will very happy to help you further.
Thanks.
12 thoughts on “Logical Reasoning / Number Series Questions and Answers – III”