These formulas and problems are really helpful to crack various competitive exams in INDIA, just solve the following problems.
Formulas to remember for Time and Distance problems
1. Keep in mind only s=vt (distance= velocity X time ) derive other from this only.
2. Always give attention to units. remember only 1km/hr = 5/18 m/s [ to convert Km/hr to m/s (smaller unit) you have to multiply with small fraction i.e. 5/18 ]
3. Relative velocity – imagine the problem and add or substrata the velocities according to problem (if moving toward each other then add the velocities, If moving in same direction substrata the velocities)
4. Suppose a man covers a distance at velocity x m/s and an returns the same path at at y m/s, then the average speed during the whole journey is (2xy/x+y)m/s
5. Always solve problem by assuming variable like x and solve to find its value.
Now solve the following problem. It will be 100 time better if you keep pen and paper now. Even if you think you can solve the problem, you should try to get the answer by your own attempt now. You will be master in time and distance problems for all the exam like cat, mat, managements, Bank PO, railways etc exam after solving following problems.
1. Superheroes Liza and Tamar leave the same camp and run in opposite directions. Liza runs 1 mile per second (mps) and Tamar runs 2 mps. How far apart are they in miles after 1 hour?
Ans- opposite direction velocity, so add velocities=> v(r)= 1+2= 3 mps, from s= vt, s= 3*3600=10800 mile(remember to convert hr in second)
2. Two trains, 200 and 160 meters long take 1 minute to cross each other while traveling in the same direction and take only 10 seconds when they cross in opposite directions. What are the speeds at which the trains are traveling?
Ans- S= 200+160= 360. from x=vt, 360= (x+y)*10, 360= (x-y)60, => x= 21, y= 15
3. A ship went on a voyage after 180 miles a plane started with 10 times speed that of the ship. Find the distance when they meet from starting point.
Ans- 180 + (d/10) = d d = 20 ans is 180+20= 200 miles.
4. A person covered some distance in 12 hours. He covered half the distance by rail @ 75 km per hour and the rest by car @ 45 km/hr. The total distance covered by him was
ans- 676 km.
5. A train crosses a pole in 15 seconds, while it crosses 100 meter long platform in 25 seconds. The length of the train is –
6. Sanjay wants to reach the Railway station at 10.00 am. The station is 10 km away from his house. If Satish walks at the speed of 4 km/hour at what time shall he start from his home?
7. A man covers a distance on bike .If He had he moved 3kmph faster he would have taken 40 min less. If he had moved 2kmph slower he would have taken 40min more.the distance is.
add both equestion, solving gives v= 12, from 1st equestion, s=40 8.
8. A person starts from hill top A, goes downhill, then along a plain and finally climbs to hill top B. He takes a total of 4 hours for the jouney travelling downhill @72kmph, on plains @63kmph and uphill @56kmph. However while returning back, from B to A, he takes 4 hours 40 mins with speeds being same. Find distance AB [CAT Examination question]
Ans- 273 km
9.Rita covers a certain distance by a car traveling at a speed of 70 km/h and returns at the starting point riding on a scooter at the speed of 55 km/h. Find her average speed for the whole journey.
10.- A man and a woman 81 miles apart from each other, start traveling towards each other at the same time. If the man covers 5 miles per hour to the women’s 4 miles per hour, how far will the woman have traveled when they meet?
Time taken to meet = Distance between them / Relative speed
= 81/(4 + 5) = 9 hours
Therefore, woman travells = 9 x 4 = 36 miles.
11..A boat goes 50 Km upstream in 10 hours and a distance of 40 Km. Down stream is 9 hours. The speed of the boat in standing water is
After solving above problem you can easily crack the Time and Distance problems asked at TCS, infosys, wipro etc. You can find similar questions at RS Agarwal Book.