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Mileage
Posted: Mon Jul 14, 2014 3:52 pm
by Ian Volante
While driving northwards last night, I noticed my milometer click over to a palindromic total. 11 miles later, it was again palindromic. After driving a further 17 miles, it won't now be palindromic again for 9,993 miles. How many miles has my car covered?
Re: Mileage
Posted: Mon Jul 14, 2014 4:42 pm
by Gavin Chipper
If it had travelled 199991 miles, then after another 11 it would be on 200002 (also palindromic). Then after another 17 miles, it would be on 200019, but you didn't specify that this number had to be palindromic. Another 9993 miles later and it will be 210012. So the answer is 200019.
Re: Mileage
Posted: Mon Jul 14, 2014 4:44 pm
by Graeme Cole
Ian Volante wrote:After driving a further 17 miles, it won't now be palindromic again for 9,993 miles.
Don't you mean 1,083?
Re: Mileage
Posted: Mon Jul 14, 2014 4:52 pm
by Graeme Cole
Gavin Chipper wrote:If it had travelled 199991 miles, then after another 11 it would be on 200002 (also palindromic). Then after another 17 miles, it would be on 200019, but you didn't specify that this number had to be palindromic. Another 9993 miles later and it will be 210012. So the answer is 200019.
I had 100018, but I was counting 099990 as palindromic.
Re: Mileage
Posted: Tue Jul 15, 2014 10:42 am
by Ian Volante
Well done Mr Chipper. You are correct. Want to buy a car?
Graeme, counting leading zeroes would just have been perverse
Re: Mileage
Posted: Tue Jul 15, 2014 11:11 am
by Gavin Chipper
Ian Volante wrote:Well done Mr Chipper. You are correct. Want to buy a car?
Graeme, counting leading zeroes would just have been perverse
Depends. How many miles has it done?
Counting leading zeroes isn't that perverse given that milometers show them - particularly old ones!