Aptitude - Time and Distance - Discussion
Discussion Forum : Time and Distance - General Questions (Q.No. 8)
8.
The ratio between the speeds of two trains is 7 : 8. If the second train runs 400 km in 4 hours, then the speed of the first train is:
Answer: Option
Explanation:
Let the speed of two trains be 7x and 8x km/hr.
| Then, 8x = |  |
400 |  |
= 100 |
| 4 |
 x = |
|
100 | |
= 12.5 |
| 8 |
Speed of first train = (7 x 12.5) km/hr = 87.5 km/hr.
Discussion:
51 comments Page 2 of 6.
Nayan vekariya said:
6 years ago
Fast solve to other method :
Two train ratio 7:8
First train speed = 400 km /4 hour
= 100 km/h
Ratio 8 ---------------> 100 km
Ratio of 7 ------------> ?
7 *100 / 8 = 87.5 km/p.
That answer is 87.5.
Two train ratio 7:8
First train speed = 400 km /4 hour
= 100 km/h
Ratio 8 ---------------> 100 km
Ratio of 7 ------------> ?
7 *100 / 8 = 87.5 km/p.
That answer is 87.5.
(8)
Ophi said:
1 decade ago
Step 1 :
Find the speed of the Second train.
Runs at 400kms in 4 hours, S=D/T.
400/4 = 100kms/hr.
Step 2 :
Find the speed of first train.
Let speed of first train be "x".
By comparing the Ratio.
7:8 = x:100.
Then 8x = 7*100.
x = 700/8.
= 87.5km/hr.
Find the speed of the Second train.
Runs at 400kms in 4 hours, S=D/T.
400/4 = 100kms/hr.
Step 2 :
Find the speed of first train.
Let speed of first train be "x".
By comparing the Ratio.
7:8 = x:100.
Then 8x = 7*100.
x = 700/8.
= 87.5km/hr.
VIJETH bk said:
1 year ago
The Speed of a second train is:
400/4 = 100km/hr.
The Ratio that is given if the speed is 7:8;
=> 7 : 8 = x : 100.
X is the speed of the first train and 100 is the speed of the second train.
7/8 = x/100.
X = 7×100/8.
X = 87.5km/hr.
400/4 = 100km/hr.
The Ratio that is given if the speed is 7:8;
=> 7 : 8 = x : 100.
X is the speed of the first train and 100 is the speed of the second train.
7/8 = x/100.
X = 7×100/8.
X = 87.5km/hr.
(18)
Meghan Desai said:
2 years ago
@all.
Here is an easy explanation;
So,
speed of second car = D/T = 400/4 =100kmph.
Now we have;
7:8::x:100 (let the speed of the first car is x)
i.e
7/8 = x/100
Therefore,
8x=700;
x = 700/8 &
x = 87.5kmph.
Thank you!
Here is an easy explanation;
So,
speed of second car = D/T = 400/4 =100kmph.
Now we have;
7:8::x:100 (let the speed of the first car is x)
i.e
7/8 = x/100
Therefore,
8x=700;
x = 700/8 &
x = 87.5kmph.
Thank you!
(46)
Nikkyy said:
7 years ago
We know that speed = distance/time,
let speed be x km/hr.
we are calculating speed for 2nd train,
x=400/4,
x =100,
Give ratio of speeds is 7 and 8.
so taking this,
8----------->100.
7------------> x ?.
x=(7*100)/8,
x=87.5km/hr.
let speed be x km/hr.
we are calculating speed for 2nd train,
x=400/4,
x =100,
Give ratio of speeds is 7 and 8.
so taking this,
8----------->100.
7------------> x ?.
x=(7*100)/8,
x=87.5km/hr.
Soumya said:
7 years ago
s1: s2= 7: 8.
The speed of the second train = distance/time = 400/4 =100.
This 100 corresponds to 8.
7: 8 * 12.5 = 100
Since 7:8 is a ratio, it will get multiplied to the same number only, therefore 7 * 12.5 = 87.5.
The speed of the second train = distance/time = 400/4 =100.
This 100 corresponds to 8.
7: 8 * 12.5 = 100
Since 7:8 is a ratio, it will get multiplied to the same number only, therefore 7 * 12.5 = 87.5.
Utkarsh kohapare said:
6 years ago
Simply;
Speed=distance/time.
s=400/4 i.e = 100kmph speed of second train.
The ratio is 7:8
Therefore 8 ------> 100
7 ------> x.
Solving it we get 8x=700.
x = 700/8 = 87.5.
Speed=distance/time.
s=400/4 i.e = 100kmph speed of second train.
The ratio is 7:8
Therefore 8 ------> 100
7 ------> x.
Solving it we get 8x=700.
x = 700/8 = 87.5.
Prabhat Kumar said:
6 years ago
Ratio of 1st & 2nd train = 7:8
Let speed of the first train x.
2nd train speed = 400/4 = 100km/hr.
And for 1st train.
7:8::x:100.
8x = 700.
X = 700/8 = 87.5 km/hr.
So 1st train speed 87.5 km/hr.
Let speed of the first train x.
2nd train speed = 400/4 = 100km/hr.
And for 1st train.
7:8::x:100.
8x = 700.
X = 700/8 = 87.5 km/hr.
So 1st train speed 87.5 km/hr.
(7)
Neha said:
6 years ago
Hey guys can anyone help me to solve this problem?
Nilesh goes to school from the village at the speed of 4km/hr and returns at the speed of 2km/hr. Find the distance from his village to the school.
Nilesh goes to school from the village at the speed of 4km/hr and returns at the speed of 2km/hr. Find the distance from his village to the school.
(1)
Avnish poddar said:
1 decade ago
Let speed of first train is "x"
And speed of second train is ""y"
Therefore given ratio are (x/y) = (7/8).
x = (7/8)*y = 87.5 kmph : Answer.
Where y =(400/4) = 100.
And speed of second train is ""y"
Therefore given ratio are (x/y) = (7/8).
x = (7/8)*y = 87.5 kmph : Answer.
Where y =(400/4) = 100.
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