A bus travels at a speed of 40 km/hr to a destination & returns back at a speed of 60 km/hr. The average speed during the complete journey is km/hr.  

This question was previously asked in
NPCIL Assistant Grade-1 (HR/F&A/C&MM/Steno Grade-I) Official Paper-II (Held In: 2022)
View all NPCIL Assistant Grade 1 Papers >
  1. 50
  2. 48
  3. 46
  4. 42

Answer (Detailed Solution Below)

Option 2 : 48
Free
NPCIL Assistant Grade 1 Computer Knowledge Subject Test - 01
0.5 K Users
20 Questions 60 Marks 15 Mins

Detailed Solution

Download Solution PDF

Given:

Speed when bus goes A to B = 40 km/h

Speed when bus returns B from A = 60 km/h

So, Average speed = (2 × 40 × 60)/(40 + 60)

⇒ Average speed = (2 × 40 × 60)/100

⇒ Average speed = 48 km/h

∴ The average speed of the bus is 48 km/h.

Hence, "Option 2" is the correct answer.

Additional InformationFormula used:

Average speed = 2ab/(a + b)

a = Speed a object when it goes from A to B.

b = Speed of a object when it returns same place

Formula is only used when the distance travels by all the speed is equal.

Important Points 1) When the two speed are given,

Average speed =  2xy/(x + y)

2) When three speeds are given,

Average speed = 3xyz/(xy + yz + zx)

Note: All the above formula is only used when the distance travels by all the speed is equal.

Latest NPCIL Assistant Grade 1 Updates

Last updated on Mar 21, 2025

-> Nuclear Power Corporation of India Limited has published a comprehensive notification for the position of NPCIL Assistant Grade 1.

-> A total of 37 vacancies has been announced for the post of NPCIL Assistant Grade 1. Bookmark this page for all the latest updates.

-> Interested applicants can start submitting their online applications from 12 March 2025.

-> The application window will be closed on 1 April 2025. However the date of exam is yet to be notified.

-> Candidates can review the NPCIL Assistant Grade 1 Previous Year Papers, for better preparation!

More Quant Based Puzzle Questions

Get Free Access Now
Hot Links: teen patti vungo teen patti tiger teen patti bindaas