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Topic review (newest first)

jacks
2012-12-24 02:06:37

Thanks friends got it

phrontister
2012-12-22 21:53:52

Hi,

a = 2...from d x 4 = even, and a x 4 must be a single-digit result (to avoid a 5-digit end product).
b = 1...from b x 4 must be a single-digit result (to keep a = 2), and 2 is already taken.
d = 8...from a x 4 = 8.
c = 7...from (c x 4) + the tens unit (3) from d x 4 must end in 1, which is only possible with c = 7 or 2; but 2 is already taken.

So, abcd is 2178.

bobbym
2012-12-22 06:20:41

Hi;

First thing that jumps right out at you is that the front digit is either a 1 or 2. So, the last digit is a 4 or an 8. You now only have to try 16 numbers to find all the answers.

jacks
2012-12-22 06:11:18

Yes 2178 is right answer.

How can i get it.

would you like to explain me

hanks

bobbym
2012-12-22 05:48:18

Hi;

Yes, and that is the only solution.

anonimnystefy
2012-12-22 05:33:17

I have that abcd=2178.

jacks
2012-12-22 05:15:13

A 4 digit no. abcd is such that 4 *(abcd) = (dcba). Then no. abcd is

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