A motorcar does a journey in 10 hrs, the first half at 21 kmph and the second half at 24 kmph. Find the distance?
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220
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222
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224
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226
Let total distance = 2x. Time for first half = x/21, second half = x/24. Total time = x/21 + x/24 = x(8/168 + 7/168) = 15x/168 = 5x/56. Speed = distance/time = 2x/(5x/56) = 112/5 = 22.4 kmph. Distance = speed×time = 22.4×10 = 224 km.
To find the distance traveled by the motorcar, we can use the formula:
Distance = Speed x Time
Let's calculate the distance for each half of the journey:
First half of the journey: Speed = 21 km/h Time = 10/2 = 5 hours
Distance for the first half = Speed x Time = 21 km/h x 5 hours = 105 km
Second half of the journey: Speed = 24 km/h Time = 10/2 = 5 hours
Distance for the second half = Speed x Time = 24 km/h x 5 hours = 120 km
Total distance traveled by the motorcar = Distance for the first half + Distance for the second half = 105 km + 120 km = 225 km
Therefore, the correct answer is C) 224.