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Kaushal travelled for 12 hours 55 minutes at the speed of 24 km/h. At what speed (in km/h) should he travel to cover the same distance in 5 hours?
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62 Question ID : 441009545460 Option 1 ID : 4410092137239 Option 2 ID : 4410092137238 Option 3 ID : 4410092137237 Option 4 ID : 4410092137236 Status : Answered Chosen Option : D
62 Question ID : 441009545460 Option 1 ID : 4410092137239 Option 2 ID : 4410092137238 Option 3 ID : 4410092137237 Option 4 ID : 4410092137236 Status : Answered Chosen Option : D
Use the inverse proportion property: since distance is constant, S1├ЧT1=S2├ЧT2. Convert minutes to fraction of an hour: 126055тАЛ=121211тАЛ=12155тАЛ hours.
Time taken T1 = 12 hours 55 minutes, Speed S1 = 24 km/h, New Time T2 = 5 hours.
D=S├ЧT
Use the inverse proportion property: since distance is constant, S1├ЧT1=S2├ЧT2. Convert minutes to fraction of an hour: 126055тАЛ=121211тАЛ=12155тАЛ hours.
Students often treat 12 hours 55 minutes as 12.55 hours instead of converting 55 minutes into 6055тАЛ hours.
Convert total time into hours
Convert 12 hours 55 minutes to hours: T1=12+6055тАЛ=12+1211тАЛ=12144+11тАЛ=12155тАЛ hours.
T1=12155тАЛ┬аhours
Calculate the total distance
Since Distance D=S1├ЧT1, calculate D=24├Ч12155тАЛ.
D=24├Ч12155тАЛ=2├Ч155=310┬аkm
Calculate new speed
To cover the same distance D=310 km in T2=5 hours, use S2=T2DтАЛ.
S2=5310тАЛ=62┬аkm/h
D is correct because calculating the total distance as 310 km and dividing by the new time of 5 hours results in 62 km/h.
This inverse relationship SтИЭT1тАЛ is also fundamental in work and wages problems where work is equivalent to distance and workers are equivalent to speed.