Speed, Time and Distance
 For every 4 leaps taken by a dog, a cat takes 5 leaps in the same time. But distance covered in 3 leaps of dog is same as that of 4 leaps of cat. Then what is the ratio of speed of dog and cat ?

 15 : 14
 16 :15
 12 :11
 10 : 9

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Ratio of speed of dog and cat = Ratio of distance covered by them in the same time
Correct Option: B
Let distance covered by dog in 1 leap is x and
Distance covered by cat in 1 leap is y
Then, 3x = 4y
∴ x= 4/3y
Now, Ratio of speed of dog and cat = Ratio of distance covered by them in the same time = 4x : 5y
= 16/3y : 5y
= 16 : 15
 Suresh traveled 1200 km by air which formed (2/5) of his trip. Onethird of the whole trip he traveled by car And the rest of the journey he performed by train. The distance traveled by train was ?

 1600 km.
 800 km.
 1800 km.
 400 km.

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Let the total distance be y km.
Then, 2y / 5 = 1200
⇒ y = (1200 x 5) /2 = 3000 km.
Distance traveled by car
= (1/3 X 3000) = 1000 km.Correct Option: B
Let the total distance be y km.
Then, 2y / 5 = 1200
⇒ y = (1200 x 5) /2 = 3000 km.
Distance traveled by car
= (1/3 X 3000) = 1000 km.
Distance traveled by train
= [3000 (1200 + 1000) ] km.
= 800 km.
 Two cyclists A and B start from the same place at the same time. One going toward north at 18 km/hr. and other going toward south at 20 km/hr. What time will they take to be 95 km. apart ?

 4 hrs. 30 min.
 4 hrs. 45 min.
 5 hrs.16 min.
 2hrs. 30 min

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Relative velocity = u + v = 18 + 20 = 38 km
They are 38 km. apart in 1 hr.Correct Option: D
Relative velocity = u + v = 18 + 20 = 38 km
They are 38 km. apart in 1 hr.
∴ They will be 95 km. apart in ( 95 / 38) hrs.
= 2 hrs . 30 min
 A bullock cart has to cover a distance of 80 km. in 10 hours. If it cover half of journey in 3/5^{th} time, what should be its speed to cover the remaining distance in time left ?

 8 km/hr.
 20 km/hr.
 6.4 km/hr.
 10 km/hr.

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Distance left = (1/2 x 80 ) km. = 40km.
Time left  [(13/5) x 10 ] hrs.
= 4 hoursCorrect Option: D
Distance left = (1/2 x 80 ) km. = 40km.
Time left  [(13/5) x 10 ] hrs.
= 4 hours
Required speed = (40 / 4 ) km/hr
= 10 km/hr.
 The ratio between the rates of travelling of A and B is 2:3 and therefore A takes 10 min. more than the time taken by B to reach a destination, if A had walked at double the speed, he would have covered the distance in ?

 30 min
 25 min
 15 min
 20 Min

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Ratio of times taken by A and B = 1/2 : 1/3
Suppose B takes T_{b} min. Then A takes (T_{b} + 10) min.
∴ (T_{b} + 10 ) : T_{b} = 1/2: 1/3
⇒ (T_{b} + 10)/T_{b} = 3 / 2
⇒ 2T_{b} + 20 = 3T_{b}
∴ T_{b} = 20
Correct Option: C
Ratio of times taken by A and B = 1/2 : 1/3
Suppose B takes T_{b} min. Then A takes (T_{b} + 10) min.
∴ (T_{b} + 10 ) : T_{b} = 1/2: 1/3
⇒ (T_{b} + 10)/T_{b} = 3 / 2
⇒ 2T_{b} + 20 = 3T_{b}
∴ T_{b} = 20
∴ Time taken by A = 20 +10
= 30 minute
If A had walked at double speed
Req . time = 30/2
=15 minute