# Quantitative Aptitude : Number Series Set 84

Directions(1-5): Find the wrong number of the following number series.

1. 7, 9, 16, 25, 41, 68, 107, 173
07
9
7
68
173
Option D
16 = 9 + 7
25 = 16 + 9
41 = 25 + 16
66 = 41 + 25
68 is wrong and it should be replaced by 66.

2. 16, 19, 21, 30, 46, 71, 107
71
21
30
107
19
Option E
107 – 71 = 36 = 6^2
71 – 46 = 25 = 5^2
46 – 30 = 16 = 4^2
30 – 21 = 9 = 3^2
21 – 17 = 2^2
19 is wrong and it should be replaced by 17.

3. 4, 2, 3.5, 7.5, 26.25, 118.125
7.5
2
3.5
18.125
4
Option C
*0.5
*1.5
*2.5
*3.5
*4.5
3.5 is wrong and it should be replaced by 3.

4. 16, 4, 2, 1.5, 1.75, 1.875
1.875
1.75
16
1.5
2
Option B
*0.25
*0.5
*0.75
*1
*1.25
1.75 is wrong and it should be replaced by 1.5.

5. 2, 11, 38, 197, 1172, 8227, 65806
11
8227
1172
2
38
Option C
11 = 2 × 3 + 5
38 = 11 × 4 – 6
197 = 38 × 5 + 7
197 × 6 – 8
1172 is wrong and it should be replaced by 197 × 6 – 8 = 1174.

6. Directions(6-10): Find the missing term of the following series.

7. 15, 12, 17, 10, ?, 8, 21, 6
16
19
14
13
10
Option B
-3
+5
-7
+9
-11
+13
-15
? = 19

8. 1, ?, 27, 64, 125
11
8
10
7
9
Option B
1 = l^3
? = 2^3= 8
27 = 3^3
64 = 4^3
125 = 5^3

9. 2, 5, 7, 12, 19, 31, 50,?
77
62
70
81
66
Option D
2 + 5 = 7
7 + 5 = 12
12 + 7 = 19
19 + 12 = 31
31 + 19 = 50
50 + 31 = 81

10. 4, 6, 12, 30, 90, 315, ?
1100
1120
1260
1352
1450
Option C
*1.5
*2
*2.5
*3
*3.5
*4
? = 1260

11. 1, 6, 36, 240, 1960, ?
18850
17755
18230
19660
17250
Option D
1 × 2 + 2 × 2 = 6
6 × 4 + 4 × 3 = 36
36 × 6 + 6 × 4 = 240
240 × 8 + 8 × 5 = 1960
1960 × 10 + 10 × 6 = 19660