Question:In a 100 m race, A runs at 8 km per hour. If A gives B a start of 4 m and still beats him by 15 seconds, what is the speed of B ?
Answer Time taken by A to cover 100 m` = ((60 xx 60)/8000 xx 100) sec.` = 45 sec. :. B covers (100 - 4) m = 96 m in (45 + 15) sec = 60 sec. :. B's speed` = ((96 xx 60 xx 60)/(60 xx 1000))` km/hr = 5.76 km/hr.
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In a 100 m race, A runs at 8 km per hour. If A gives B a start of 4 m and still beats him by 15 seconds, what is the speed of B ?