Skip to main content

Accenture Sample Problems On Speed

Below are three problems dealing with speed and time calculations.

Question 1
Two buses leaving from two stations 20 km away from each other travel with constant speed of 45km/hr towards each other.Find the time taken to cross each other if the length of each bus is 100m.
a)10sec b)4sec c)15sec d)20sec
Answer : b)4sec
Solution :
The time taken to cross each other = (a + b) / (u + v) sec.
Here, a = b = length of the two buses = 100m = 1/10 km.
and u = v = speed of the two buses = 45km/hr.
Time taken to cross each other = (a + b) / (u + v) sec = (1/10 + 1/10) / (45 + 45) hours
1 / (10 x 90) = 1/900 hours.
since 1 hour = 3600 sec, 1/900 hour = 3600/900 = 4 sec
Hence the answer is 4 sec.

Question 2
A bus starts from A at 7 a.m and reaches the destination B at 7.30 a.m while a cyclist starts from B at 7 a.m and reaches A at 8.30 a.m. At what time the bus and the cyclist will cross each other?
a)7.34 a.m b)7.49 a.m c)7.23 a.m d)8.01 a.m
Answer : c)7.23a.m
Solution :
Let the distance between A and B is X km
Time taken by the bus to cover X km = 1/2 hour .(i.e., 7 a.m to 7.30 a.m)
Time taken by the cyclist to cover X km = 3/2 hour (i.e., 7 a.m to 8.30 a.m)
Speed = distance / time
Speed of the bus = X / 1/2 = 2X km/hr
And the speed of the cyclist = X / 3/2 = 2X / 3 km/hr.
Let they meet at point C at Y hours after 7 a.m.
Distance covered by the bus in Y hours = Speed X Time = 2XY km = AC
And the distance covered by the cyclist in Y hours = Speed x Time = 2XY/3 km = BC
Since C is the point where Bus and Cyclist cross each other, AC + BC = AB
In other words, 2XY + (2/3)XY = X
Y(2 + 2/3) = 1
Y = 3/8 hours.
Expressing in minutes, Y = 3/8 x 60 minutes = 22.5 minutes
Y = 23 minutes (approximately)
Therefore they meet at 7 a.m + 23 minutes = 7.23 a.m
Hence the answer is 7.23 a.m.

Question 3
A man rides a bike with a constant speed of 20 km/hr from A at 4 p.m and travels towards a destination B. Another rider with a speed of 25 km/hr starts from B at 5 p.m and travels towards A. If the straight distance between A and B is 110km then at what time they will meet?
a)7 p.m b)8 p.m c)7.30 p.m d)6 p.m
Answer : a)7 p.m
Solution :
Let the two riders meet at X hours after 4 p.m.
Speed of the first rider is 20km/hr and the distance covered by him in X hours = 20X km
Speed of the 2nd rider is 25 Km/hr and he starts at 5 p.m.
Distance covered by him in (X - 1) hours = 25(X - 1) km
Distance between A and B is 110km.
Therefore 20X + 25(X - 1) = 110
45X = 135
X = 135/45 = 3
So they meet at 3 hours after 4 p.m.
Hence the answer is 7 p.m.

Comments

Popular posts from this blog

Introduction to JavaScript- Basics

JavaScript is the most popular scripting language on the internet, and works in all major browsers, such as Internet Explorer, Firefox, Chrome, Opera, and Safari. What You Should Already Know Before you continue you should have a basic understanding of the following: HTML and CSS If you want to study these subjects first, find the tutorials on our Languages page . What is JavaScript? JavaScript was designed to add interactivity to HTML pages JavaScript is a scripting language A scripting language is a lightweight programming language JavaScript is usually embedded directly into HTML pages JavaScript is an interpreted language (means that scripts execute without preliminary compilation) Everyone can use JavaScript without purchasing a license Are Java and JavaScript the same? NO! Java and JavaScript are two completely different languages in both concept and design! Java (developed by Sun Microsystems) is a powerful and much more complex programming language ...

IBM Sample Problem Using Speed

Question 1 A policeman starts chasing a thief 30 minutes after the thief had run from a spot. With an average speed of 20km per hour, he takes 2 hours to catch the thief. What is the average speed of the thief? a)16km/hr b)25km/hr c)24km/hr d)18km/hr Answer : a)16km/hr Solution: As given, the average speed of the policeman = 20km/hr. He takes 2 hours to catch the thief, so from formula, "distance = speed x time" we have The total distance covered by the police to catch the thief = 20 x 2 = 40 km (This value is also equal to the distance run by thief before being caught by Police.) Policeman had started late by 30 minutes and took 2 hours to catch the running thief. Above means that the thief takes (30minutes + 2 hours =) 5/2 hours to reach 40km. So the speed of the thief = 40/(5/2) = 40 x 2 / 5 = 16 km/hr. Hence the answer is 16km/hr. Question 2 From a particular spot, Tom started to chase Jerry which had left the spot before 30 minutes. Tom ran acro...

MCA - Syllabus, Notes, Question Papers, Projects

MCA - Syllabus, Notes, Question Papers, Projects : SEMESTER - 1 Syllabus: Syllabus PDF Notes: Semester 1 Notes Question Papers:  Project: SEMESTER - 2 Syllabus: Syllabus PDF                                   Notes: Semester 2 Notes Question Papers:  Projects:  SEMESTER - 3  Syllabus: Syllabus PDF                                   Notes: Semester 3 Notes Question Papers:  Project: SEMESTER - 4  Syllabus: Syllabus PDF                               ...