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December 13th, 2011, 12:54 AM   #1
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no. of digit

The no. which is of the form which is divisible by

where are digits.
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December 13th, 2011, 02:31 AM   #2
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Re: no. of digit

Quote:
Originally Posted by panky
The no. which is of the form which is divisible by

where are digits.
x=4 and y=2, that is, 34452 or x=0 and y=6, that is, 34056
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December 13th, 2011, 08:39 AM   #3
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Re: no. of digit

Also x=9, y=6: 34956
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December 13th, 2011, 08:45 AM   #4
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Re: no. of digit

If a number is divisible by 36 then it is divisible by 4 and 9.

To be divisible by 4, then the number formed by the two rightmost digits will be divisible by 4. 52 and 56 are divisible by 4, so y may be either 2 or 6.

If a number is divisible by 9, then the sum of its digits is divisible by 9. 3 + 4 + 5 = 12, so x + y = 6 or x + y = 15. So we have 3 possibilities:

(x,y) = (0,6), (4,2), (9,6)

34056

34452

34956
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