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A train enters into a tunnel AB at A and...

A train enters into a tunnel AB at A and exits at B. A jackal is sitting at O in another by passing tunnel AOB, which is connected to AB at A and B, where OA is perpendicular to OB. A cat is sitting at P inside the tunnel AB making the shortest possible distance between O and P, such that AO : PB = 30 : 32. When a train before entering into the tunnel AB makes a whistle (or siren) somewhere before A, the jackal and cat run towards A, they meet with accident (with the train) at the entrance A. Further if the cat moves towards B instead of A it again meets with accident at the exit of the tunnel by the same train coming from the same direaction.
The ratio of speeds of jackal is to train is :

A

`5:1`

B

`3:5`

C

`1:5`

D

can't be determined

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AI Generated Solution

The correct Answer is:
To solve the problem, we will break it down into steps to find the ratio of the speeds of the jackal to the train. ### Step 1: Understand the Distances We have two tunnels: tunnel AB where the train travels and tunnel AOB where the jackal is located. The distances are given in the ratio AO:PB = 30:32. Let: - AO = 30k (for some constant k) - PB = 32k ### Step 2: Determine the Total Distance The total distance from point O to point B can be calculated as: - OB = OA + AB = AO + PB = 30k + 32k = 62k. ### Step 3: Analyze the Movement Towards A When the train whistles before entering tunnel A, both the jackal and the cat run towards point A. The distances they travel are: - Jackal travels from O to A (30k). - Cat travels from P to A (which is PB = 32k). ### Step 4: Time Taken to Reach A Let the speed of the jackal be Vj and the speed of the train be Vt. The time taken by both the jackal and the cat to reach point A when the train reaches A is the same. Using the formula: \[ \text{Time} = \frac{\text{Distance}}{\text{Speed}} \] For the jackal: \[ t = \frac{30k}{Vj} \] For the cat: \[ t = \frac{32k}{Vc} \] Since both times are equal: \[ \frac{30k}{Vj} = \frac{32k}{Vc} \] ### Step 5: Analyze the Movement Towards B If the cat instead runs towards B, it still meets with the train at point B. The distance from A to B is the length of the tunnel, which we will denote as L. The jackal travels from O to B, which is the total distance OB = 62k. ### Step 6: Calculate the Time Taken to Reach B For the jackal: \[ t = \frac{62k}{Vj} \] For the train: \[ t = \frac{L}{Vt} \] ### Step 7: Set Up the Equations Since the time taken for both scenarios (running towards A and running towards B) is equal, we can set up the equations: 1. From A to A: \[ \frac{30k}{Vj} = \frac{32k}{Vc} \] 2. From A to B: \[ \frac{62k}{Vj} = \frac{L}{Vt} \] ### Step 8: Solve for the Ratios From the first equation, we can express the ratio of speeds: \[ \frac{Vj}{Vc} = \frac{30}{32} = \frac{15}{16} \] From the second equation, we can express the ratio of speeds: \[ \frac{Vj}{Vt} = \frac{62k}{L} \] ### Step 9: Find the Final Ratio To find the ratio of the speeds of the jackal to the train, we need to combine the ratios we have derived. Assuming L = 50 (length of the tunnel AB), we can substitute: \[ \frac{Vj}{Vt} = \frac{62k}{50} \] ### Step 10: Final Calculation Now, we can find the ratio of the speeds of the jackal to the train: \[ \frac{Vj}{Vt} = \frac{10}{50} = \frac{1}{5} \] Thus, the ratio of the speeds of the jackal to the train is: **1:5**
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A train enters into a tunnel AB at A and exits at B. A jackal is sitting at 0 in another by-passing tunnel AOB, which is connected to AB at A and B, where OA is perpendicular to OB. A cat s sitting at P inside the tunnel AB making the shortest possible distance between O and P, such that AO=30 km and PB=32 km. when a train before entering into the tunnel AB makes a whistle (or siren’) somewhere before A ,the Jackal and cat run towards A. they meet with accident with the train) at the entrance A. The ratio of speeds of jackal and cat is:

A train enters into a tunnel AB at A and exits at B. A jackal is sitting at 0 in another by-passing tunnel AOB, which is connected to AB at A and B, where OA is perpendicular to OB. A cat s sitting at P inside the tunnel AB making the shortest possible distance between O and P, such that AO=30 km and PB=32 km. when a train before entering into the tunnel AB makes a whistle (or siren’) somewhere before A ,the Jackal and cat run towards A. they meet with accident with the train) at the entrance A. The ratio of speeds of jackal and cat is

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