Question
A train travelling at the speed of 72 km/hr crosses
another train, having 60 meters less length and travelling in opposite direction at the speed of 54 km/hr in 6 seconds. If the longer train crosses a platform in 12 seconds, then the shorter train will cross the same platform in how many seconds?Solution
Speed of longer train = 72 × (5/18) = 20 m/s
Speed of shorter train = 54 × (5/18) = 15 m/s
Let length of longer and shorter trains be ‘L’ meters and (L – 60) metres, respectively.
According to question,
L + L – 60 = (20 + 15) × 6 = 210
2L – 60 = 210
L = 135 metres
So, L – 60 = 75 metres
Let length of platform is ‘P’ metres
So, P + 135 = 20 × 12 = 240
P = 240 – 135 = 105 meters
Desired time = (105 + 75)/15 = 180/15 = 12 seconds
A person X wants to distribute some pens among six children A, B, C, D, E and F. Suppose A gets twice the number of pens received by B, three times tha...
A bill for ₹1,840 is paid in the denominations of ₹50, ₹20 and ₹10 notes. 50 notes in all are used. Consider the following statements:
There are two Classes A and B having 25 and 30 students respectively. In Class-A the highest score is 21 and lowest score is 17. In Class-B the highest...
Two candidates X and Y contested an election. 80% of voters cast their vote and there were no invalid votes. There was no NOTA (None of the above) opti...
Joseph visits the club on every 5th day, Harsh visits on every 24th day, while Sumit visits on every 9th day. If all three of them met at th...
A Statement followed by Conclusion - I and Conclusion - II is given below. You have to take the Statement to be true even if it seems to be at variance...
If the price of an article is decreased by 20% and then the new price is increased by 25%, then what is the net change in the price?
Jay and Vijay spent an equal amount of money to buy some pens and special pencils of the same quality from the same store. If Jay bought 3 pens and 5 p...
The difference between a 2-digit number and the number obtained by interchanging the positions of the digits is 54.
Consider the following sta...
There are two containers X and Y. X contains 100 ml of milk and Y contains 100 ml of water. 20 ml of milk from X is transferred to V. After mixing well...
