Train A crosses a 400m long bridge and a pole in 32 second and 12 seconds respectively. If length of train B is 40m more then the length of train A and speed of train B is 32m/sec. Then how much time required if train A and B is running in opposite direction ?
14 sec
4 sec
18 sec
10 sec
19 sec
Option D Let length of train A = x x+400/32 = x/12 32x = 12x + 4800 20x = 4800 x = 240 speed of train A = 240/12 = 20m/sec length of train B = 240 + 40 = 280m speed of train B = 32m/sec Time = 240 + 280/32 + 20 = 520/52 = 10sec
The ratio of number of male and female in a group is 8 : 5. If the percentage of male and female increased by 20% and 25% respectively. Then find the new ratio of male and female, if total number of male and female is 260 initially.
8 : 3
5 : 4
7 : 8
5 : 3
4 : 11
Option D Total number of male and female = 260 number of male = 260 * 8/13 = 160 number of female = 260 * 5/13 = 100 increased male = 160 * 5/4= 200 increased female = 100 * 6/5 = 120 ratio = 200 : 120 = 5 : 3
The ratio of age of A and B before 5 years is 2 : 3 and D is 12 years elder than B. The present age of C is one fourth of the present age of D. If the age of C after 6 years is 14 years, then find the present age of B.
28 years
20 years
34 years
38 years
42 years
Option B Let the age of A and B before 5 years = 2x and 3x present age of A = 2x + 5 present age of B = 3x + 5 present age of D = 3x + 5 + 12 = 3x + 17 present age of C = 3x + 17/4 present age of C = 14 – 6 = 8 years 3x + 17/4 = 8 3x + 17 = 32 3x = 32 – 17 3x = 15 x = 5 present age of B = 3x + 5 = 20 years.
A bag contain 4 red pens, 6 green pens and 8 blue pens. If 2 pens are taken at randomly, then find the probability that there are no blue pens.
8/17
5/17
8/15
2/8
4
Option B required = 10C2 = 10 * 9/2 * 1 = 45 total = 18C2 = 18 * 17 / 2*1 = 153 probability = 45/153 = 5/17
Shiva invested rs.4200 in a scheme at 18% per annum for 3 years at simple interest and he also invested same amount in another scheme at 20% per annum for 3 years. What is the difference between simple interest and compound interest which he earned from both the scheme ?
