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CBSE Class 9 Answered

 A motorcyclist  drives A to B with a uniform speed of 30 kmph and returns back with a speed of 20kmph. Find its average speed?
Asked by jshree616 | 14 Jun, 2019, 07:35: AM
answered-by-expert Expert Answer
Let d km be the distance between locations A and B.
 
Time taken to travel from A to B = (d/30) hour
Time taken to travel from B to A = (d/20) hour
 
average speed = Total_Distance/time  =  begin mathsize 14px style equals space fraction numerator 2 d space k m over denominator open parentheses d over 30 plus d over 20 close parentheses h r end fraction space equals space fraction numerator space space space space space 2 d space k m space space space space space over denominator begin display style fraction numerator 5 d over denominator 60 end fraction end style space h r end fraction space equals space 24 space k m divided by h r end style
Answered by Thiyagarajan K | 14 Jun, 2019, 08:58: AM

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CBSE 9 - Physics
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CBSE 9 - Physics
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Asked by mailtoparvathyprajith | 06 Feb, 2024, 09:50: PM
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CBSE 9 - Physics
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