# Quant Test for IBPS PO Prelims Exam set – 30

1. A well with 28 m inside diameter is dug out 18 m deep. The earth taken out of it has been evenly spread all around it to a width of 21 m to form an embarkment. Find the height of the embarkment.
3
6
2
4
7
Option A
22/7[(R2) – (r2)] * h = 22/7(7*7*18)
[(352) – (72)]h = 14 * 14 * 18
(42*28)h = 14*14*18
h = 3 m

2. Raj is 25 years old. If Suraj’s age is 25% greater than that of Raj then how much percent Raj’s age is less than Suraj’s age?
50%
20%
40%
30%
60%
Option B
Percentage decrease = 25/125 * 100 = 20%

3. The population of a village has increased annually at the rate of 20%. If at the end of 3 years it is 21600, the population in the beginning of the first year?
12200
11245
12500
12000
12450
Option C
21600 = P*(1 + 20/100)^3
= 12500

4. A Person borrows Rs. 8000 at 20% compound rate of interest. At the end of each year he pays back Rs. 3000. How much amount should he pay at the end of the third year to clear all his dues?
4560
4620
5500
5904
4000
Option D
At the end of 1st year = 8000+1600= 9600
Amount = 9600 – 3000 = 6600
At the end of 2nd year = 6600+1320 = 7920
Amount = 7920 – 3000 = 4920
Amount to be paid at the end of 3rd year = 4920 + 984 = 5904

5. 12 Persons are seated at a circular table. Find the probability that 3 particular persons always seated together.
7/55
6/55
3/55
4/55
2/55
Option C
Total probability = (12-1)! = 11!
Desired probability = (10 – 1)! = 9!
So, p = (9! *3!) /11! = 3/55

6. Directions(6-10): Find the wrong number of the following series.

7. 4 6 18 49 201 1011
201
49
6
18
1011
Option D
4 × 1 + 2 = 4 + 2 = 6
6 × 2 + 3 = 12 + 3 = 15 == 18
15 × 3 + 4 = 45 + 4 = 49
49 × 4 + 5 = 196 + 5 = 201
201 × 5 + 6 = 1005 + 6 = 1011

8. 48 72 108 162 243 366
48
72
108
366
243
Option D
48 ×3/2 = 72; 72 ×3/2 = 108
108 × 3/2= 162: 162 × 3/2 = 243
243 ×3/2 = 364.5 == 366

9. 2 54 300 1220 3674 7350
1220
300
3674
2
54
Option C
2 × 6 + 7 × 6 = 12 + 42 = 54
54 × 5 + 6 × 5 = 270 + 30 = 300
300 × 4 + 5 × 4 = 1200 + 20 = 1220
1220 × 3 + 4 × 3 = 3660 + 12
= 3672 == 3674
3672 × 2 + 3 × 2 = 7344 + 6 = 7350

10. 8 27 64 125 218 343
8
64
218
27
125
Option C
2^3 = 8 : 3^3 = 27
4^3 = 64 : 5^3 = 125
6^3 = 216 == 218
7^3 = 343

11. 19 68 102 129 145 154
145
19
68
102
154
Option D
19 + 7^2 = 19 + 49 = 68
68 + 6^2 = 68 + 36 = 104== 102
104 + 5^2 = 104 + 25 = 129
129 + 4^2 = 129 + 16 = 145
145 + 3^2 = 145 + 9 = 154