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anonymous
 one year ago
how do i find the 7000th registration plate of a series of plates using numbers 0,1,2,3,5,7 and 6 OR 9
anonymous
 one year ago
how do i find the 7000th registration plate of a series of plates using numbers 0,1,2,3,5,7 and 6 OR 9

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0This is an interesting question.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0What do you think the question actually means?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Yep any ideas?? the reg. number must be 7 digits long and cannot start with a zero. The numbers go in ascending order so the first three numbers are 1023567, 1023576, 1023579

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I believe there is a bit of confusion with the way question is worded.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I think you use factorial numbers to figure it out. so number of combinations using 9 would be 5040 subtract combinations which start with zero (720) then add the combinations using 6 instead of nine and total number of combinations for reg. number is 8640 which would be the largest number possible with the combination of numbers: 9753210

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0This is very curious... I am trying my best.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Do you mind precisely showming me the original question you seem to be reiterating over and over..? It's a little confusing and I am not on the same page as you.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0A harbour has boat registration number of 7 digits. None can start with zero. the harbour has been able to get numbers 0,1,2,3,5,7,9. No digit is used more than once in a registration number. You can use the 9 as a six upside down. Both numbers 6 and 9 cannot be in the same registration number. Numbers are issued in ascending order. What is the 7000th number?

mathmate
 one year ago
Best ResponseYou've already chosen the best response.2@jimmy10 Thank you for posting the original question. It is much appreciated.

mathmate
 one year ago
Best ResponseYou've already chosen the best response.2There are 7 digits, and each number has 7 digits, so there are 7! permutations. Removing zero at the beginning, leaves us with 6(6!) permutations. Taking mutation of the 6 & 9 into account, there are 2*6(6!)=8640 permutations, which is greater than 7000, so there is a solution. Here's an idea of what I did. Check it out to make sure there are no errors. Hope someone finds a faster way of doing it (apart from using a computer program) Numbers of the form 1XXXXXX, 2XXXXXX, 3XXXXXX, 5XXXXXX take up 2*4(6!)=5760 numbers. (note: the multiplier "2" is for the mutation of the 6/9). Numbers of the form 6XXXXXX take up 6!=720 numbers (no more duplicates with 6 & 9) for a total of 6480 numbers. Numbers of the form 70XXXXX, 71XXXXX take up 2*2(5!)=480 numbers for a total of 6960 numbers Numbers of the form 720XXXX take up 2(4!) = 48 numbers, for at total of 7008 numbers. So the 7000th number must be of this form. Numbers of the form 7201XXX, 7203XXX, 7205XXX take up 2*3(3!)=36 numbers for a total of 6996 numbers The next numbers are: 7206135 7206153 7206315 7206351 (7000th number) ...
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