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Question 785327: My thousands digit is 3 times my 100's digit. The sum of my 10's and 1's digit is 1 less than my 1000's digit. My 100's digit is 2 less than my 10's digit. What 4 digit number am I? Please help! Thanks.
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! The four digits: a, b, c, d (a is the thousands)
:
My thousands digit is 3 times my 100's digit.
a = 3b
:
The sum of my 10's and 1's digit is 1 less than my 1000's digit.
c + d = a - 1
:
My 100's digit is 2 less than my 10's digit.
b = c - 2
or
c = b + 2
:
Using c + d = a - 1, replace c with (b+2), replace a with 3b
b + 2 + d = 3b - 1
d = 3b - b - 1 - 2
d = 2b - 3
:
Lets assume b = 3, then a = 9,
then
c = 3 + 2
c = 5
and
d = 2(3) - 3
d = 3
:
9353 is the number
:
or
Lets assume b = 2, then a = 6,
then
c = 2 + 2
c = 4
and
d = 2(2) - 3
d = 1
:
6241 is the number
:
I think that is the only two possibilities
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