×

# ENIGMA05 - Editorial

Help Baburao

Author and Editorialist : Dhruv Mahajan

Simple

# EXPLANATION:

Average Speed is Not (u+v)/2.

But it is (total distance covered)/(total time taken).

Let distance from A to B is 'd', then time taken from A to B is d/u. And distance between B to A will also remain 'd', hence time taken from B to A is d/v.

Total distance covered in the journey is 2d. Hence average speed will be (total distance covered)/(total time taken), which is (2d)/(d/u+d/v) which is equal to 2uv/(u+v).

Remember if u=0 and v=0 then avg speed will also be zero.

# SOLUTIONS

This question is marked "community wiki".

464
accept rate: 10%

 0 Why was this contest not listed in the Contests section? answered 16 Oct '15, 18:36 31●2 accept rate: 0% It was a Closed Contest. (16 Oct '15, 23:06)
 toggle preview community wiki:
Preview

By Email:

Markdown Basics

• *italic* or _italic_
• **bold** or __bold__
• image?![alt text](/path/img.jpg "title")
• numbered list: 1. Foo 2. Bar
• to add a line break simply add two spaces to where you would like the new line to be.
• basic HTML tags are also supported
• mathemetical formulas in Latex between \$ symbol

Question tags:

×15,852
×1,191
×968
×42

question asked: 16 Oct '15, 18:26

question was seen: 767 times

last updated: 16 Oct '15, 23:27