Question

difficult combination question

Answer 1

The Gladstone harbour board decides to issue private boats uusing the Gladstone harbour with 7 digit registration numbers. None of these can start with zero. The harbour board had only been able to get the digits 0, 1, 2, 3, 4, 5, 7, 9 for the boat registration numbers. No digit may be used more than once in each registration number. Bruno, who was responsible for allocating the registration numbers to the boats, had the bright idea of using the number 9 upside down to make 6. However, the 6 and 9 cannot both occur in th same registration number. The registration numbers are issued in ascending orider. Thus the first registration number is 1023567. The next two are 1023576 and 1023679. How many boats can have registration numbers staring with 1

Answer 2

"the 6 and 9 cannot both occur in th same registration number."

yet its given that: 1023679 is a registration number
^ ^
thats breaking the rules ....