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A dog takes 4 leaps for every 5 leaps of hare but 3 leaps of dog is equal to 4 leaps of hare compare speed?
Ans is 16:15 ...how
Read Solution (Total 7)
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- Let the distance covered by dog in 1 leap is x and hare covered 1 leap is y.
then, 3x = 4y
=> x =(4/3) y
=> 4x =(16/3) y
Then, The ratio of speeds of dog and hare = Ratio of distances covered by them in the same time
= 4x : 5y
= (16/3)y : 5y
=(16/3) : 5
= 16:15
Ans=16:15 - 10 years agoHelpfull: Yes(47) No(0)
- May be this shortcut works for you...
actual speed of A:B
given speed of A given speed of B
----------------------------------- :---------------------
no.of steps of A in terms of length no.of steps of B in terms of length.
dog:hare=(4/3):(5/4)=16:15 - 10 years agoHelpfull: Yes(19) No(0)
- 4:5 :: 3:4 so if u know ratio and proportion this equlas 4*4/5*3=16/15
- 10 years agoHelpfull: Yes(3) No(0)
- let the distance covered in 1 leap of dog be x meters
let the distance covered in 1 leap of hare be y meters.
it is given that 3 leaps of dog is equal to 4 leaps of hare.
so, 3x=4y
y=(3/4)x ------(1)
for a period of time, say t seconds, it is given that dog takes 4 leaps for every 5 leaps of hare.
speed of hare= dist/time = 5y/t m/sec
speed of dog= dist/time = 4x/t m/sec
ratio of their speeds= speed of dog/speed of hare
= 4x/5y
= 4x/15x/4 ---------(from (1) substituting y=(3/4)x)
= 16/15 - 10 years agoHelpfull: Yes(2) No(0)
- In the point of time
4x=5y------1
In the point of distance 3:4
3x=4y. =>. x=4y/3. => 4x=16y/3
Speed of dog to hare using eq1
4x=5y then 16y/3=5y. =16:15 - 10 years agoHelpfull: Yes(1) No(0)
- 4/5*4/3=16/15
- 10 years agoHelpfull: Yes(0) No(1)
- speed of dog=3/4;
speed of hare=4/5;
relative speed=(3/4)/(4/5)=15:16 - 10 years agoHelpfull: Yes(0) No(3)
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