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When a positive integer N is written in base 9, it is a two-digit number. Wnen 6N is written in base 7, it is a three-digit number obtained from the two-digit number by writing 4 to its right. Find the decimal representations of all such numbers N.

Does that mean the two-digit number of base 9 and the three-digit number of base 7 both contain one "4"?
Please explain.

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Originally posted by ardnas
When a positive integer N is written in base 9, it is a two-digit number. Wnen 6N is written in base 7, it is a three-digit number obtained from the two-digit number by writing 4 to its right. Find the decimal representations of all such numbers N.

Does that mean the two-digit number of base 9 and the three-digit number of base 7 both contain one "4"?
Please explain.
By 6N do you mean 6xN or the 6N (as in concatenation of N after 6)?

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Originally posted by ardnas
When a positive integer N is written in base 9, it is a two-digit number. Wnen 6N is written in base 7, it is a three-digit number obtained from the two-digit number by writing 4 to its right. Find the decimal representations of all such numbers N.

Does that mean the two-digit number of base 9 and the three-digit number of base 7 both contain one "4"?
Please explain.
OK, here's my list of numbers (decimal - Nbase9/6*Nbase7):

10 - 11/114
24 - 26/264

So it's not necessary to have a 4 in both numbers. Explaination to follow when I figure it out.


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There is only one decimal number that fits this construct. The two digit number does not contain a 4. Should I PM you with the number or just post it?

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Originally posted by jebry
There is only one decimal number that fits this construct. The two digit number does not contain a 4. Should I PM you with the number or just post it?
Please email me with it, thanks!

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