# Logical Reasoning / Number Series Questions and Answers – VII

The article has 24 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.

## Questions Section

Q1. Here is the number series to solve, if:
50 + 55 = 5250
74 + 54 = 9472
43 + 13 = 2408
97 + 14 = ? – what will be the number here?

Logic for other number:
50(50+55) =5250,
74(74+54) =9472
43(43+13) =2408
Logic: The logic is addition of both number multiplied by first number i.e.(50 + 55)*50=5250

Q2. Second question in the series is:
93 + 24 = 6417
6 + 71 = -390
22 + 86 = -1408
55 + 54 = ? – what will be the number here?

Logic to see how other numbers were derived in above series: 93(93-24) =6417,
6(6-71) =-390,
22(22-86) =-1408
Logic: The logic is subtraction of both number multiplied by first number i.e.(93 – 24)*93=6417

Q3. Third question in the series is:
10 + 32 = 52
98 + 17 = 213
22 + 47 = 91
97 + 49 = ? – what will be the number here?

Logic for other numbers:
10*2+32 =52,
98*2+17 =213,
22*2+47 =91
Logic: The logic is 2 multiplied by first number plus second number i.e.(10*2 + 32)=52

Q4. What is the next number in the series:

66, 33.0, 16.5, 8.25, ?

Logic: Second number is half of first one, 3rd number is half of second one and so on i.e.
66/2 =33.0,
33.0/2 =16.5,
16.5/2 =8.25
and so on.

Q5. Guess next number in the series:

8, 4.0, ??, 1.0, 0.5

Logic: Second number is half of first one, 3rd number is half of second one and so on i.e.
8/2 = 4.0,
4.0/2 = 2.0,
2.0/2 =1.0
and so on.

Q6. Guess next number in the series:

6, 36, 216, 1296, ?

Logic: The series is square, cube, ^4 and so on i.e.
6*6 = 36 ,
6*6*6 = 216 etc.
or you can say next number is previous number multiplied by 6.

Q7. Guess next number in the series:

8, 64, ??, 4096, 32768

Logic: The series is square, cube, ^4 and so on i.e.
8*8 = 64, ,
8*8*8 = 512 etc.
or simply you can say next number is previous number multiplied by 8.

Q8. Guess next number in the series:
7, 8, 10, 13, ?

Ans. 17 i.e. 13 + 4
Logic: Second number is (1st number + 1), third number is (2nd number + 2), 4th is (3rd number + 3) and so on.
i.e.
7 + 1 = 8,
8 + 2 = 10,
10 + 3 = 13 and so on.

Q9. What will be the next number in the series:
1, 3, 7, 13, ?

Ans. 21 i.e. 12 + 8
Logic: Second number is (1st number + 2), third number is (2nd number + 4), 4th is (3rd number + 6) and so on.
1 + 2 = 3,
3 + 4 = 7,
7 + 6 = 13
and so on.

Q10. Find the missing number in the series:
19, 21, ??, 31, 39

Ans. 25 i.e.21 + 4
19+2=21,
21+4=25,
25+6=31,
31+8=39,
Logic: Second number is (1st number + 2), third number is (2nd number + 4), 4th is (3rd number + 6) and so on.

Q11. Find the next number in the series is:

-446, -449, -452, -455, ??

Ans: -458 i.e. -455 – 3 = -458
Simple subtraction series:
-446,
-446 – 3 = -449,
-449 – 3 = -452,
-452 – 3 = -452,
-452 – 3 = -455,
and so on.
Logic: Every number is previous number minus 3 and that is how you can identify the last number in the series.

Q12. Find the next number in the series is:

454, 473, 492, 511, ??

Ans: 530 i.e. 511 + 19 = 530
454,
454 + 19 = 473,
473 + 19 = 492,
492 + 19 = 492,
492 + 19 = 511,
and so on.
Logic: Every number is previous number plus 19 and that is how you can find out the last number in the series.

Q13. Find the next number in the series is:

588, 577, 566, 555, ??, 533

Ans: 544 i.e. 555 – 11 = 544
Subtraction series:
588,
588 – 11 = 577,
577 – 11 = 566,
566 – 11 = 566,
566 – 11 = 555,
and so on.
Logic: Every number is previous number minus 11 and that is how the middle number or the number at 5th position will be identified.

Q14. Find the next number in the series is:

-838, -825, -812, -799, ??, -773

Ans: -786 i.e. -799 + 13 = -786
-838,
-838 + 13 = -825,
-825 + 13 = -812,
-812 + 13 = -812,
-812 + 13 = -799,
and so on.
Logic: Every number is previous number plus 13 and that is how you can find out the number at 5th position.

Q15. Find the next number in the series is:

-572, -579, -586, -593, ??

Ans: -600 i.e. -593 – 7 = -600
Subtraction series:
-572,
-572 – 7 = -579,
-579 – 7 = -586,
-586 – 7 = -586,
-586 – 7 = -593,
and so on.
Logic: Every number is previous number minus 7 and that is how you can identify the last number in the series.

Q16. Find the next number in the series is:

778, 785, 792, 799, ??

Ans: 806 i.e. 799 + 7 = 806
778,
778 + 7 = 785,
785 + 7 = 792,
792 + 7 = 799,
and so on.
Logic: Every number is previous number plus 7 and that is how you can find out the last number in the series.

Q17. Find the next number in the series is:

928, 911, 894, 877, ??, 843

Ans: 860 i.e. 877 – 17 = 860
Subtraction series:
928,
928 – 17 = 911,
911 – 17 = 894,
894 – 17 = 894,
894 – 17 = 877,
and so on.
Logic: Every number is previous number minus 17 and that is how the middle number or the number at 5th position will be identified.

Q18. Find the next number in the series is:

-674, -666, -658, -650, ??, -634

Ans: -642 i.e. -650 + 8 = -642
-674,
-674 + 8 = -666,
-666 + 8 = -658,
-658 + 8 = -658,
-658 + 8 = -650,
and so on.
Logic: Every number is previous number plus 8 and that is how you can find out the number at 5th position.

Q19. Find the next number in the series is:

-864, -865, -866, -867, ??

Ans: -868 i.e. -867 – 1 = -868
Subtraction series:
-864,
-864 – 1 = -865,
-865 – 1 = -866,
-866 – 1 = -866,
-866 – 1 = -867,
and so on.
Logic: Every number is previous number minus 1 and that is how you can identify the last number in the series.

Q20. Find the next number in the series is:

820, 838, 856, 874, ??

Ans: 892 i.e. 874 + 18 = 892
820,
820 + 18 = 838,
838 + 18 = 856,
856 + 18 = 856,
856 + 18 = 874,
and so on.
Logic: Every number is previous number plus 18 and that is how you can find out the last number in the series.

Q21. Find the next number in the series is:

314, 296, 278, 260, ??, 224

Ans: 242 i.e. 260 – 18 = 242
Subtraction series:
314,
314 – 18 = 296,
296 – 18 = 278,
278 – 18 = 278,
278 – 18 = 260,
and so on.
Logic: Every number is previous number minus 18 and that is how the middle number or the number at 5th position will be identified.

Q22. Find the next number in the series is:

-340, -323, -306, -289, ??, -255

Ans: -272 i.e. -289 + 17 = -272
-340,
-340 + 17 = -323,
-323 + 17 = -306,
-306 + 17 = -306,
-306 + 17 = -289,
and so on.
Logic: Every number is previous number plus 17 and that is how you can find out the number at 5th position.

Q23. Find the next number in the series is:

-34, -35, -36, -37, ??

Ans: -38 i.e. -37 – 1 = -38
Simple subtraction series:
-34,
-34 – 1 = -35,
-35 – 1 = -36,
-36 – 1 = -36,
-36 – 1 = -37,
and so on.
Logic: Every number is previous number minus 1 and that is how you can idenify the last number in the series.

Q24. Find the next number in the series is:

844, 852, 860, 868, ??

Ans: 876 i.e. 868 + 8 = 876
844,
844 + 8 = 852,
852 + 8 = 860,
860 + 8 = 860,
860 + 8 = 868,
and so on.
Logic: Every number is previous number plus 8 and that is how you can find out the last number in the series.

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