Answers

  • Brainly User
2014-05-16T18:42:05+05:30
let the car travels a distance x km at 50 km/h. 
=> x/50 hours. 
as car travels the same distance x km at 40 km/h. 
=> x/40 hours. 
Total distance= 2x km 
Total time= x/50 + x/40 hs 
Avg speed = Total dist. / Total time
=> 2x / (x/50 + x/40)  
=> 2 * 50 * 40 / (50 + 40)
=> 44.4 km/h
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hey, i did not understand the last 3 steps.. can u show me in detail !!
=> 2x / (x/50 + x/40)
=> 2x / (90x/50*40)
=> 2x50x40 / 90
2014-05-16T21:58:29+05:30
Distance=x/40+x/50,speeds are 50x and 40x
Avg. speed =total speed/distance
=2*50*40x^2/(50+40)x^2
=44.44 km/hr
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