The Best tricky interview questions which requires presence of mind

Interviewer: There is one scooter (2 wheeler) which has one stepney/spare tire (so totally 3 tyres). Each tyre can run up to maximum of 5 km.

How long will the bike run till?

Candidate's Answer:
"Obviously, 5 km." This is the answer from the candidate as he/she thought that the scooter can't run with a single tire. But the answer he has given is wrong. Hope you find the answer now. He also did some calculation and confirmed the answer as 7.5 km. Do you know now?

First run 2.5 km and change the 1st tyre with stepney. Now some life (kms) remains in 1st tyre: 2.5 km, 2nd tyre: 2.5 km, Stepney : 5 km

Again run for 2.5 km and this time change 2nd tyre with 1st tyre: Now some life (kms) remains in 1st tyre: 2.5 km, 2nd tyre :0 km ,stepney : 2.5 km.

Now run 2.5 km with remaining 1st tyre and stepney .

Total: 2.5+2.5+2.5=7.5

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