There is a square field of side 10m. A man runs with different speed 10kmph, 15kmph, 20kmph, 25kmph on the four sides of the field. What is the average speed of man

• avg speed =total distance /total time....0.04/(0.01/10+0.01/15+0.01/20+0.01/25)=15.58kmph
• 11 years agoHelpfull: Yes(26) No(3)
• @Rudra
  total distance to be covered= 4(10m)=40m=0.04km
  total time=sum of individual times
  =>(0.01/10)+(0.01/15)+(0.01/20)+(0.01/25)=0.77/300
  avg speed =total distance /total time= 0.04/(0.77/300)=15.58kmph
  
• 11 years agoHelpfull: Yes(22) No(1)
• Average speed = 2*a*b/a+b
  Now for first two terms we have a=10, b=15
  so average= 2*10*15/25=12kmph
  Now we have a=12 and b= 20 ,so average= 2*12*20/32=15kmph
  and lastly we have a=15 and b= 25 so average= 2*15*25/40= 75/4= 18.75kmph..
• 11 years agoHelpfull: Yes(7) No(10)
• sorry my earlier interpretation was wrong..sry
• 11 years agoHelpfull: Yes(1) No(0)
• why not 17.5?
  (10+15+20+25)/4=17.5
• 11 years agoHelpfull: Yes(1) No(8)
• @ROHIN PLZZZZ EXAPLAIN IN DETAIL..........
• 11 years agoHelpfull: Yes(0) No(0)
• @VEMAVARAPU MOULIKA Thank you very much!!!!!
• 11 years agoHelpfull: Yes(0) No(0)
• Average speed = 15.58 kmph.
• 11 years agoHelpfull: Yes(0) No(0)