# Logical Reasoning / Number Series Questions and Answers – VIII

The article has 19 questions on “Logical Reasoning / Number Series Questions and Answers” series where you will find different number series questions followed by some number is getting added or subtracted.

You have to identify the missing number in the series.

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Odd Man out: Part – I | Part II.

Numbers rules the universe.
– Pythagoras

## Questions Section

Q1. Find the next number in the series is:

48, 42, 36, 30, ??, 18

Ans: 24 i.e. 30 – 6 = 24
Simple subtraction series:
48,
48 – 6 = 42,
42 – 6 = 36,
36 – 6 = 36,
36 – 6 = 30,
and so on.
Logic: Every number is previous number minus 6 and that is how the middle number or the number at 5th position will be identified.

Q2. Find the next number in the series is:

-204, -187, -170, -153, ??, -119

Ans: -136 i.e. -153 + 17 = -136
-204,
-204 + 17 = -187,
-187 + 17 = -170,
-170 + 17 = -170,
-170 + 17 = -153,
and so on.
Logic: Every number is previous number plus 17 and that is how you can find out the number at 5th position.

Q3. Find the next number in the series is:

-742, -750, -758, -766, ??

Ans: -774 i.e. -766 – 8 = -774
Simple subtraction series:
-742,
-742 – 8 = -750,
-750 – 8 = -758,
-758 – 8 = -758,
-758 – 8 = -766,
and so on.
Logic: Every number is previous number minus 8 and that is how you can identify the last number in the series.

Q4. Find the next number in the series is:

888, 893, 898, 903, ??

Ans: 908 i.e. 903 + 5 = 908
888,
888 + 5 = 893,
893 + 5 = 898,
898 + 5 = 898,
898 + 5 = 903,
and so on.
Logic: Every number is previous number plus 5 and that is how you can find out the last number in the series.

Q5. Find the next number in the series is:

178, 168, 158, 148, ??, 128

Ans: 138 i.e. 148 – 10 = 138
Simple subtraction series:
178,
178 – 10 = 168,
168 – 10 = 158,
158 – 10 = 158,
158 – 10 = 148,
and so on.
Logic: Every number is previous number minus 10 and that is how the middle number or the number at 5th position will be identified.

Do you know which metal is the best conductor of electricity?
Ans: Silver

Q6. Find the next number in the series is:

-964, -958, -952, -946, ??, -934

Ans: -940 i.e. -946 + 6 = -940
-964,
-964 + 6 = -958,
-958 + 6 = -952,
-952 + 6 = -952,
-952 + 6 = -946,
and so on.
Logic: Every number is previous number plus 6 and that is how you can find out the number at 5th position.

Q7. Find the next number in the series is:

-22, -26, -30, -34, ??

Ans: -38 i.e. -34 – 4 = -38
Simple subtraction series:
-22,
-22 – 4 = -26,
-26 – 4 = -30,
-30 – 4 = -30,
-30 – 4 = -34,
and so on.
Logic: Every number is previous number minus 4 and that is how you can identify the last number in the series.

Q8. Find the next number in the series is:

94, 103, 112, 121, ??

Ans: 130 i.e. 121 + 9 = 130
94,
94 + 9 = 103,
103 + 9 = 112,
112 + 9 = 112,
112 + 9 = 121,
and so on.
Logic: Every number is previous number plus 9 and that is how you can find out the last number in the series.

Q9. Find the next number in the series is:

612, 611, 610, 609, ??, 607

Ans: 608 i.e. 609 – 1 = 608
612,
612 – 1 = 611,
611 – 1 = 610,
610 – 1 = 610,
610 – 1 = 609,
and so on.
Logic: Every number is previous number minus 1 and that is how the middle number or the number at 5th position will be identified.

Q10. Find the next number in the series is:

-334, -328, -322, -316, ??, -304

Ans: -310 i.e. -316 + 6 = -310
-334,
-334 + 6 = -328,
-328 + 6 = -322,
-322 + 6 = -322,
-322 + 6 = -316,
and so on.
Logic: Every number is previous number plus 6 and that is how you can find out the number at 5th position.

Do you know which is the hardest form of carbon?
Ans: Diamond

Q11. Identify the missing number in the series:
2, 5, ??, 11, 14, 17

Ans. 8 i.e.5 + 3
2+3=5,
5+3=8,
8+3=11,
11+3=14,
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:
24, 27, ??, 36, 42, 49

Ans. 31 i.e.27 + 4
Series explanation:
24+3=27,
27+4=31,
31+5=36,
36+6=42,
42+7=49,
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:
8, 8, ??, 48, 192, 960

Ans.16 i.e.8*2=16,

Series explanation:
8*1 = 8,
8*2 = 16,
16*3 = 48,
48*4 = 192,
192*5 = 960,
Logic: First number1 = 2nd number, second number2 = 3rd number, third number*3 = 4th number and so on.

Q14. Find the missing number in the series:
6,14 ,21 ,?? ,35,42

Ans.28 i.e.(6*4+4)=28
6*2+2=14,
6*3+3=21,
6*4+4=28,
6*5+5=35,
6*6+6=42.
Logic: 1st number *2 + 2 = second, 1st number * 3 + 3 = third, 1st number * 4 + 4 = fourth and so on.

Q15. A car crosses a 1100 m long road in 8 minutes. What will be it’s speed in km per hour?
Options: A. 2.72, B. 4.125, C. 4.95, D. 8.25

Answer: 8.25 km/h i.e. [(1100/1000) / (8/60)]
Logic: Converting 1100 to kilometer by dividing it by 1000 and converting 8 to hour by dividing it by 60 and dividing both.

Q16. Next number in the series is:

28, 31 , 29, 32, 30, ??

Ans: 33 i.e. 30 + 3 = 33
Alternate subtraction series:
28,
28 + 3 = 31,
31 – 2 =29
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.

Q17. Next number in the series is:

0, -2 , -6, -8, -12, ??

Ans: -14 i.e. -12 – 2 = -14
Alternate subtraction series:
0,
0 – 2 = -2,
-2 – 4 =-6
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.

Q18. Next number in the series is:

24, 23 , 25, 24, 26, ??

Ans: 25 i.e. 26 – 1 = 25
24,
24 – 1 = 23,
23 +2 =25
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.

Q19. Next number in the series is:

0, 0 , -11, -11, -22, ??

Ans: -22 i.e. -11 – 11 = -22
Explanation:
0,
0,
0 -11 = -11,
0 -11 = -11
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.

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