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If not, let us be your guide.
The answer is 25000 Kms. Let’s see how…
- Let the car move on ABCD for the first 5000 Kms.
- Then swap A with S, and move 5000 kms.
- Then reinsert A and swap B with S.
- Similarly, swap C and D with S while reinserting the tyre taken out in previous process at 15000 and 20000 Kms.
- During the final journey, the tyre A B C and S will carry the car for 5000 Kms before finally wearing off.
So, the Car can travel 25000 kms like this.