How long the scooter Tyre run?
Answer: 7.5 KM
Explanation: First run 2.5 km and change the 1st tyre with stepney. Now 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 kms remains 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