Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 31)
31.
Two, trains, one from Howrah to Patna and the other from Patna to Howrah, start simultaneously. After they meet, the trains reach their destinations after 9 hours and 16 hours respectively. The ratio of their speeds is:
Answer: Option
Explanation:
Let us name the trains as A and B. Then,
(A's speed) : (B's speed) = b : a = 16 : 9 = 4 : 3.
Discussion:
108 comments Page 1 of 11.
Aishwarya Kolekar said:
2 weeks ago
Very good to practise. Thanks all.
Amarendra Kumar said:
7 months ago
Good. Thanks everyone for explaining the answer.
(2)
Gaurav Dandagaval said:
10 months ago
Nice, Thanks all.
(2)
Vrushabh shivle said:
10 months ago
Here we can use the ratio method:
Train 1 ( Howrah to Patna) = A.
Train 2 ( Patna to Howrah) = B/
Ratio of speed = √speed of A/ √speed of B
= √16/√9.
= 4/3.
That is the answer is 4 : 3.
Train 1 ( Howrah to Patna) = A.
Train 2 ( Patna to Howrah) = B/
Ratio of speed = √speed of A/ √speed of B
= √16/√9.
= 4/3.
That is the answer is 4 : 3.
(2)
Abhilasha Varshney said:
11 months ago
Let's suppose the train meets after x hours.
speed of train1 = s1 and speed of train2 =s2,
So, distance covered by train1 in x hours = xs1 and distance covered by train2 in x hours = xs2.
So total distance from Howrah to Patna(d)=xs1+xs2.
After they meet, they reach their destination after 9 and 16 hours respectively.
So, speed of train1 =d/x+9 and speed of train2=d/x+16
So, s1=xs1+xs2/x+9 and s1x+9s1=xs1+xs2, x=9s1/s2,
speed of train2=d/x+16.
So s2=xs1+xs2/x+16, xs2+16s2=xs1+xs2.
x=16s2/s1, 9s1/s2 = 16s2/s1,(s1/s2)^2 = 16/9.
So, s1/s2 = 4/3.
speed of train1 = s1 and speed of train2 =s2,
So, distance covered by train1 in x hours = xs1 and distance covered by train2 in x hours = xs2.
So total distance from Howrah to Patna(d)=xs1+xs2.
After they meet, they reach their destination after 9 and 16 hours respectively.
So, speed of train1 =d/x+9 and speed of train2=d/x+16
So, s1=xs1+xs2/x+9 and s1x+9s1=xs1+xs2, x=9s1/s2,
speed of train2=d/x+16.
So s2=xs1+xs2/x+16, xs2+16s2=xs1+xs2.
x=16s2/s1, 9s1/s2 = 16s2/s1,(s1/s2)^2 = 16/9.
So, s1/s2 = 4/3.
(41)
Vijaya banu said:
1 year ago
Very useful. Thanks for the explanation.
(4)
Keerthana said:
1 year ago
Thank you for giving useful questions.
(6)
Gayathri said:
1 year ago
Thanks everyone for explaining the answer.
(1)
Swathi said:
2 years ago
Well done, Thanks all for explaining the answer.
(3)
Aashaka said:
2 years ago
@All.
Speed of a train = speed of another train x √T1/T2.
So the ratio of speed = speed of train/speed of another train = √T1/T2.
So, we can get directly, 4:3.
Speed of a train = speed of another train x √T1/T2.
So the ratio of speed = speed of train/speed of another train = √T1/T2.
So, we can get directly, 4:3.
(6)
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