Bissoy.com
Doctors Medicines MCQs Q&A

A man is travelling in his car from city A to B and back. In the journey from A to B he is travelling with constant speed of 40 km/hr. While travelling back his speed was 45 km/hr. He took 3 hrs in the whole journey. What was his average speed?

A man is travelling in his car from city A to B and back. In the journey from A to B he is travelling with constant speed of 40 km/hr. While travelling back his speed was 45 km/hr. He took 3 hrs in the whole journey. What was his average speed? Correct Answer 42.4 km/hr

Let time taken from A to B be x hrs.

∴ Time taken from B to A is (3 – x) hrs

Distance between A to B = Distance between B to A

⇒ 40 × x = 45 × (3 - x)

⇒ 40x + 45x = 135

⇒ x = 135/85 = 1.59 hrs

∴ Total distance = 2(40 × x) = 2 × 40 × 1.59 = 127.2 km

∴ Average speed = 127.2/3 = 42.4 km/hr

Related Questions

The parking rates of car in a railway station parking are depicted as follows: (a) Up to 2 hrs – Rs. 50 (b) More than 2 hrs and up to 5 hrs – Rs. 75 (c) After 5 hrs – Rs. 10 per extra hour up to 8 hrs. (d) More than 8 hrs and up to 12 hrs – Rs. 150 (e) More than 12 hrs and up to 24 hrs – Rs. 250 Rajeev parks his car at 7.00 a.m. and comes back to pick it up at 4.30 p.m. on the same day. How much money does he have to pay?
Each of the question below consists of a question and three statements number I, II and III given below it. You have to decide whether the data provided in the statement are sufficient to answer the question. If the bus is travelling from Surat to Ahmadabad and a car is travelling from Ahmadabad to Surat, then what is the distance between Surat and Ahmadabad? I. The speed of a car is 40% less than the speed of bus. Bus started at 9 am and car started at 10 am and they meet at 3 pm of the same day. II. After travelling for 1 hour, because of traffic average speed of bus is decreased by 20% and covers distance between Surat to Ahmadabad in 11 hours. Original speed of car is 20% less than original speed of bus and before crossing bus it covered 200 km if starts 1 hour later than bus. After crossing car, bus covers remaining distance in 5 hours. III. Speed of bus is 10 km/hr more than the speed of car and before crossing car ratio of distances covered bus and car in same time was 5 : 4. Time taken by car to cover the distance between Ahmadabad and Surat is 2 hours 15 minutes more than time taken by bus to cover the same distance.
On a journey, Mohan drove from City P to city Q to city R. His average speed for the whole journey was 20 km/hr. Find the average speed on his journey from city Q to city R. I: Average speed during the journey from city P to city Q is 20 km/hr. II: Total time taken for the entire journey is 7 hours. III: Ratio of distance traveled while going from P to Q and Q to R is 3 : 4.
The rate of waiting room per hour is depicted as follows, (a) Up to 2 hrs – Rs. 150 (b) More than 2 hrs and up to 5 hrs – Rs. 275 (c) After 5 hrs – Rs. 50 per extra hour up to 8 hrs. (d) More than 8 hrs and up to 12 hrs – Rs. 450 (e) More than 12 hrs and up to 24 hrs – Rs. 600 Rohan comes to the waiting room on Monday at 7:00 p.m. and takes leave from it on Tuesday at 5:45 p.m. in the same week. How much money does he have to pay?
Suresh plans a trip from city A to city B which are ‘x’ km apart and returning to city A. There are two light traffic zones of 25 km length each where he goes at a speed of 20 km/hr and returns at a speed of 25 km/hr. There are two heavy traffic zones of 35 km length each where he goes with a speed of 14 km/hr and returns at a speed of 21 km/ hr. For other part of the journey he maintains his speed at 90 km/hr while going and 60 km/hr while returning. If it took 2 hrs extra to go to city B from city A than to return from city B to city A, what is the approximate average speed with he was moving during his return journey (in km/hr)?
Three cars start from point A together and reach point B at equal intervals. Second car whose sped is less than third car but more than first car taken a u turn and starts its journey towards A whereas third car heads for point C which is 100 km away from point B. First car and third car meet each other at mid way of A and C after third car takes u turn from C. First car travels half the distance between A and B when second reaches B. The sum of speed of second car and third car is 100 kmh.  What is the difference between speed of third car and first car?
The question below is followed by three statements I, II, and III. You have to determine whether the data given is sufficient for answering the question. You should use the data and your knowledge of mathematics to choose the best possible answer. A car travels from city P to city Q in T hours with a speed of v km per hour. Distance between cities P and Q is D kilometers. If it increases its speed by 5 kmph it saves some time. Find the actual speed of the car. Statement I: If the car travels from P to Q with its actual speed of v kmph and come back with the speed of v + 5 kmph in 2T – 0.6 hrs Statement II: A bus start form Q at the same time when the car starts from P and the speed of the bus is 50% more than the speed of the car and the bus meets car after covering 60% of the distance Statement III: Distance between PQ is given by D2 – 25D + 200 = 0  
A man travels to four cities with four different transport as distance of 500 km in 24 hrs, 750 km in 5 hrs, 1250 km in 25 hrs and 2400 km in 12 hrs. Find the average speed (approx) of his journey if he travels to his home by walking at the end of the whole journey which is 5 km away in an hour.
In the following question, two statements are numbered as A and B. On solving these statements we get quantities A and B respectively. Solve for the both quantities and choose the correct option. Quantity A: A man covered 158 km which is half of the total distance in 3 hrs. 18 min. and completed the remaining journey at a speed of 45 km/hr. Find the average speed of his journey. Quantity B: A train completes a journey of 480 km in 10 hrs. 45 min. If the train halted for a total time of 30 min. in the whole journey, find the average speed of the train.
Monica takes 9 hrs 15 minutes in walking a distance and riding back to the same place where she started. She could walk both ways in 11 hrs 12 minutes. The time taken by her to ride back both ways is: A. 7 hrs 18 min B. 7 hrs 35 min C. 7 hrs 45 min D. 7 hrs 15 min