Question

A car travels hundred kilometre distance at a speed of 60 km per hour and returns with a speed of 40 km per hour calculate its average speed for the whole journey with the diagram

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Answer 1

Distance/speed = 100/60 hr

= (100/60)*60 = 100 mins

Speed return = 40 km/h

time taken one side = Distance/speed = 100/40 hr

= (100/40)*60 = 150 mins

Total time take = 100 + 150 = 250 min

= 250/60 hr

= 25/6 hr

Total distance = 100 + 100 = 200 km

Average speed = 200/(25/6) = 48 km/hr

Hope it helps ✅❤

Answer 2

Average speed = Total distance / Total time

=> 100+100 / t1 +t2

We know that time = d/s

=> t1 = 100/60 = 5/3

=> t2 = 100/40 = 5/2

Average speed = 200 / 5/2+5/3

=> 200 / (15+10)/6

=> 200 / 25/6

=> 200×6 / 25

=> 1200 / 25

=> 48 km/h

Average speed for whole journey = 48 km/h

Plz mark it as brainliest!!