Speed, Time and Distance
- Walking at the rate of 4 kmph a man covers certain distance in 2 hrs 45 min. Running at a speed of 16.5 kmph the man will cover the same distance in how many minutes ?
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2 hours 45 minutes
= 
2 + 45 
hours 60 = 2 + 3 hours 4 = 11 hours 4
∴ Distance = Speed × Time= 4 × 11 = 11 km. 4
∴ Time taken in covering 11 km at 16.5 kmph= 11 hour 16.5 = 11 × 10 × 60 minutes 165
= 40 minutesCorrect Option: C
2 hours 45 minutes
= 2 + 45 hours 60 = 2 + 3 hours 4 = 11 hours 4
∴ Distance = Speed × Time= 4 × 11 = 11 km. 4
∴ Time taken in covering 11 km at 16.5 kmph= 11 hour 16.5 = 11 × 10 × 60 minutes 165
= 40 minutes
- A is twice as fast as B, and B is thrice as fast as C is. The journey covered by
C in 1 1 hours will be covered by A in 2
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Time taken by C = t hours
∴ Time taken by B = t hours 3 and time taken by A = t hours 6 Here, t = 3 hours 2 ∴ Required time taken by A = 3 hour 2 6 = 1 hour 4 = 1 × 60 minutes 4
= 15 minutesCorrect Option: A
Time taken by C = t hours
∴ Time taken by B = t hours 3 and time taken by A = t hours 6 Here, t = 3 hours 2 ∴ Required time taken by A = 3 hour 2 6 = 1 hour 4 = 1 × 60 minutes 4
= 15 minutes
- A jeep is chasing a car which is 5km ahead. Their respective speed are 90 km/hr and 75 km/hr. After how many minutes will the jeep catch the car ?
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Relative speed
= 95 – 75 = 15 kmphRequired time = Distance Relative speed = 5 hours 15 = 5 × 60 minutes 15
= 20 minutesCorrect Option: B
Relative speed
= 95 – 75 = 15 kmphRequired time = Distance Relative speed = 5 hours 15 = 5 × 60 minutes 15
= 20 minutes
- A can give 40 metres start to B and 70 metres to C in a race of one kilometre How many metres start can B give to C in a race of one kilometre ?
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According to the question,
When A covers 1000m, B covers = 1000 – 40 = 960 m
and C covers =1000 – 70 = 930 m
When B covers 960m, C covers 930 m.
∴ When B covers 1000m, C covers= 930 × 1000 = 968.75 metre 960
Hence, B gives C a start of
= 1000 – 968.75 = 31.25 metreCorrect Option: B
According to the question,
When A covers 1000m, B covers = 1000 – 40 = 960 m
and C covers =1000 – 70 = 930 m
When B covers 960m, C covers 930 m.
∴ When B covers 1000m, C covers= 930 × 1000 = 968.75 metre 960
Hence, B gives C a start of
= 1000 – 968.75 = 31.25 metre
- In a race of 200 metres, B can give a start of 10 metres to A, and C can give a start of 20 metres to B. The start that C can give to A, in the same race, is
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According to the question,
∵ When B runs 200 m metres, A runs 190 metres
∴ When B runs 180 metres, A runs= 190 × 180 = 171 metres 200
When C runs 200m, B runs 180 metres.
Hence, C will give a start to A by
= 200 – 171 = 29 metresCorrect Option: C
According to the question,
∵ When B runs 200 m metres, A runs 190 metres
∴ When B runs 180 metres, A runs= 190 × 180 = 171 metres 200
When C runs 200m, B runs 180 metres.
Hence, C will give a start to A by
= 200 – 171 = 29 metres
