Ques:- Two trains of equal length when moving in opposite direction takes 5 sec. to cross each other completely and when moving in same direction takes 15 sec. Find the ratio of their speed.
Recent Answer : Added by Deven Sharma On 2023-05-31 18:18:48:
Let’s assume the length of each train is ‘L’ and the speeds of the two trains are ‘V₁’ and ‘V₂’ respectively.
When the trains are moving in the opposite direction, their relative speed is the sum of their individual speeds. The total distance they need to cover is the sum of their lengths. Since they cross each other completely in 5 seconds, we can set up the following equation:
(V₁ + V₂) × 5 = 2L
When the trains are moving in the same direction, their relative speed is the difference between their individual speeds. The total distance they need to cover is the difference between their lengths. Since they cross each other completely in 15 seconds, we can set up the following equation:
(V₁ – V₂) × 15 = 2L
Now, let’s solve these equations to find the ratio of their speeds.
From the first equation, we have:
(V₁ + V₂) × 5 = 2L
V₁ + V₂ = (2L) / 5
From the second equation, we have:
(V₁ – V₂) × 15 = 2L
V₁ – V₂ = (2L) / 15
Now, let’s substitute this value back into the first equation to find V₂:
(4L) / 15 + V₂ = (2L) / 5
V₂ = (2L) / 5 – (4L) / 15
V₂ = (6L – 4L) / 15
V₂ = (2L) / 15
Therefore, the speed of the second train is (2L) / 15.
The ratio of their speeds is given by:
(V₁ / V₂) = ((4L) / 15) / ((2L) / 15)
(V₁ / V₂) = 4L / 2L
(V₁ / V₂) = 2
So, the ratio of their speeds is 2:1.
Ques:- A sum fetched a total simple interest of Rs. 4016.25 at the rate of 9% p.a. in 5 years. What is the sum?
Recent Answer : Added by ajay On 2022-03-18 09:20:17:
8925
Ques:- A man decides to buy a nice horse. He pays $60 for it, and he is very content with the strong animal. After a year, the value of the horse has increased to $70 and he decides to sell the horse. But already a few days later he regrets his decision to sell the beautiful horse, and he buys it again. Unfortunately he has to pay $80 to get it back, so he loses $10. After another year of owning the horse, he finally decides to sell the horse for $90. What is the overall profit the man makes?
Recent Answer : Added by Meghna Bardhan On 2021-07-14 14:29:37:
$20
Ques:- Why do you want to get this job?
Ques:- Why Syntel?
Ques:- Family background & personality.
Ques:- REPUBLICAN = 108 so DEMOCRATE = ?
Recent Answer : Added by Admin On 2020-05-17 11:59:51:
democrate=1008
Ques:- Anand and Deepak started a business investing Rs. 22,500 and Rs. 35,000 respectively. Out of a total profit of Rs. 13,800, Deepak’s share is
A. Rs. 5400
B. Rs. 7200
C. Rs. 8400
D. Rs. 9600
Recent Answer : Added by Arline On 2022-03-19 16:02:11:
C
Ques:- In a class of 60, where girls are twice that of boys, Kamal ranked seventeenth from the top. If there are 9 girls ahead of Kamal, how many boys are after him in rank ?
Recent Answer : Added by Selvakumar A On 2021-10-25 09:20:31:
boys= x
girls=2x
boys+girls= 60
x+2x=60
x=60/3
x=20
kamal=17th rank
9 girls are ahead of kamal
17-9=8
20-8=12 boys are after kamal’s rank
Ques:- A and B are started a business in partnership investing Rs.20,000 and Rs.15,000 respectively. After six months, C joined them with Rs.20,000. What will be B’s share in the total profit of Rs.25,000 earned at the end of 2 years from the starting of the business?
A. Rs. 7000
B. Rs. 7500
C. Rs. 9000
D. Rs. 9500
Recent Answer : Added by Chathura On 2022-05-17 09:09:31:
A = 20k x 2y, B = 15k x 2y, C = 20k x 1.5y => 100Ky
B contribution = (15k x 2y) /100ky
B will get 0.3 from 25k which is 7.5k = 7500
Ques:- If 12 men do a work in 80 days, in how many days will 16 men do it?
Ques:- If you take a marker & start from a corner on a cube, what is the maximum number of edges you can trace across if you never trace across the same edge twice, never remove the marker from the cube, & never trace anywhere on the cube, except for the corners & edges?
Recent Answer : Added by DK BOSS On 2021-07-17 06:27:50:
Maximum number of edges = 9. Start from one corner. Select any face including that corner. Complete a square (4 edges) around the face to reach at the starting corner point . Now, move to the opposite face through the edge joining them and passing through the starting point(1 edge). Now, complete the square of edges around this face(4 edges). Total = 4+1+4 = 9 edges
Ques:- Find the least number which when divided by 35 and 11 leaves a remainder of 1 in each case.
Ques:- A single discount equivalent to the discount series of 20%, 10% and 5% is?
Recent Answer : Added by Kunal gupta On 2021-11-09 15:53:42:
Ques:- How are you helping your subordinates develop themselves?
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Ques:- An article is bought for Rs.675 and sold for Rs.900, find the gain percent?
Recent Answer : Added by Bala On 2022-09-22 16:40:04:
Gain=(profit/c.p)*100
Gain =selling price-cost price =900-675
=225.
Gain=(225/675)*100.
=33.3%
Ques:- Field experience, team handling skill, team players role, last jobs experience,job change reason.
Ques:- What is your contribution of the Branch?
Recent Answer : Added by Pallavi On 2022-04-02 06:59:53:
Very great things your doing
Ques:- Why we need to select you for this position?
Ques:- If the height of a cone is increased by 100% then it’s volume is increased by?
Ques:- How many seconds will a 500 m long train take to cross a man walking with a speed of 3 km/hr in the direction of the moving train if the speed of the train is 63 km/hr?
Recent Answer : Added by Bhoomi Patel On 2021-08-19 17:24:21:
speed of the train respect to man
= (63 – 3) km/hr
= 60 km/hr
= 60 * 1000 / 3600 m/sec
= 50/3 m/sec
time
= distance/speed
= 500 * 3/ 50
= 30 sec
Ques:- Can you work well under deadlines or pressure?
Ques:- for cube and sphere 3 views are similarly draw one such figure?
Recent Answer : Added by Admin On 2020-05-17 12:01:21:
cut a sphere in all 3 axis with center point as common point
of all axis.
u would be getting 2 lines and an arc
in other words
sphere is cut into 3 cuts in x,y,z directions
it is only similar
Ques:- P is heavier than Q but lighter than R. Q is heavier than T. S is heavier than P but lighter than V. Who among them is the lightest? (a) V (b) S (c) T (d) R (e) None of these
Recent Answer : Added by Admin On 2020-05-17 12:03:31:
R>P>Q>T
V>S>P
so the lightest is T.
Ques:- How will you measure height of building when you are at the top of the building? And if you have stone with you.
Ques:- If the numbers from 1 to 24, which are divisible by 2 are arranged in descending order, which number will be at the 8th place from the bottom?
A. 18
B. 16
C. 12
D. 10
Recent Answer : Added by Ferro On 2022-11-18 16:02:49:
1 through 24, divisible by 2 in descending order.
That leaves you with:
24, 22, 20, 18, 16, 14, 12, 10, 8, 6, 4, 2
8th place FROM the bottom means your answer will be 16.
Ques:- What will happen to the current role?
Ques:- There are five thieves, each loot a bakery one after the other such that the first one takes 1/2 of the total no. of the breads plus 1/2 of a bread. Similarly 2nd, 3rd,4th and 5th also did the same. After the fifth one no. of breads remained are 3. Initially how many breads were there?
Recent Answer : Added by Admin On 2020-05-17 11:59:42:
Friends,
The Answer given by ‘Gaurav Sharma’ is correct and
the approach (bottom to top) suggested by ‘Shailesh’ is
good. But with minor correction we can arrive the solution
using this approach:
After 5th loot, No. of breads left = 3
after 4th loot, no. of breads left = (3+0.5)x2 = 7
after 3rd loot, no. of breads left = (7+0.5)x2 = 15
after 2nd loot, no. of breads left = (15+0.5)x2 = 31
after 1st loot, no. of breads left = (31+0.5)x2 = 63
So, before 1st loot, no. of breads left = (63+0.5)x2 = 127
Let’s assume the length of each train is ‘L’ and the speeds of the two trains are ‘V₁’ and ‘V₂’ respectively.
When the trains are moving in the opposite direction, their relative speed is the sum of their individual speeds. The total distance they need to cover is the sum of their lengths. Since they cross each other completely in 5 seconds, we can set up the following equation:
(V₁ + V₂) × 5 = 2L
When the trains are moving in the same direction, their relative speed is the difference between their individual speeds. The total distance they need to cover is the difference between their lengths. Since they cross each other completely in 15 seconds, we can set up the following equation:
(V₁ – V₂) × 15 = 2L
Now, let’s solve these equations to find the ratio of their speeds.
From the first equation, we have:
(V₁ + V₂) × 5 = 2L
V₁ + V₂ = (2L) / 5
From the second equation, we have:
(V₁ – V₂) × 15 = 2L
V₁ – V₂ = (2L) / 15
Let’s add these two equations together:
V₁ + V₂ + V₁ – V₂ = (2L) / 5 + (2L) / 15
2V₁ = (6L + 2L) / 15
2V₁ = (8L) / 15
V₁ = (4L) / 15
So, the speed of the first train is (4L) / 15.
Now, let’s substitute this value back into the first equation to find V₂:
(4L) / 15 + V₂ = (2L) / 5
V₂ = (2L) / 5 – (4L) / 15
V₂ = (6L – 4L) / 15
V₂ = (2L) / 15
Therefore, the speed of the second train is (2L) / 15.
The ratio of their speeds is given by:
(V₁ / V₂) = ((4L) / 15) / ((2L) / 15)
(V₁ / V₂) = 4L / 2L
(V₁ / V₂) = 2
So, the ratio of their speeds is 2:1.