Question
Two trains running at the rates of 75 and 60 kmph
respectively, On parallel rails in opposite directions, are observed to pass each other in 12 seconds, and when they are running in the same direction at the same rate as before, a person sitting in the faster train observes that he passes the other in 90 seconds. Find the lengths of the trainsSolution
Let the length of the slower and Faster train be x and y respectively Now relative speed of train when travelling opposite direction = 75 + 60 = 135 km/hr = 135 × (5/18) m/s= 37.5 m/s Now distance covered (x) = 37.5 × 12 = 450 m ......................... (i) When travelling in same direction, relative speed = 75 – 60 = 15 km/hr = 15 × (5/18) m/s= 75/18 m/s As the time noted by the person in the faster is 90 seconds, the distance covered will be equal to the length of slower train Distance covered (y) = 75/18 × 90 = 375m ................................... (ii) From (i) and (ii) we get x= 75m
20% students (boys + girls) in a sports class are boys. Out of total boys, 45% are literate and 55 are illiterate. Find the number of literate girls in ...
'R' spends 30% of his monthly income on utilities, 35% on household expenses, and 10% of the remaining amount on transportation. He saves the rest in a ...
A and B together have total of Rs.5000 out of which they donated 10% to the orphanage school. The remaining amount is to be then redistributed between t...
In an election between two candidates, winner got 60% of total valid votes. If total number of votes cast were 1200 out of which 5% were invalid, then f...
A candidate who gets 28% marks fails by 10 marks but another candidate who gets 42% marks gets 12% more than the passing marks. Find the maximum marks.
There are two slabs of income tax, 8% tax for income up to 3 lakh and 12.5% for income above 3 lakh. Akhil tried to evade tax by hiding some of the inco...
- Ravi appeared for two papers: Physics and Chemistry. He scored 68 out of 80 in Physics and 74 out of 85 in Chemistry. Calculate his total percentage marks.
- Rohit used to earn Rs. 42,000 per month. His spending to saving ratio was 5:9. After a salary increment, he reduced his expenses by 20% and his savings inc...
Two persons A and B started working for a company in similar jobs on January 1, 1990. A's initial monthly salary was Rs 400, which increases by Rs 50 af...
The salary of a man increased from Rs. 16000 per month to Rs. 18000 per month. Find the increase percent.