MHB Find $\sqrt{ABBCDC}:$ A,B,C,D Distinct, $CDC-ABB=25$

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The problem involves finding the square root of a 6-digit number represented as $\overline{ABBCDC}$, where $ABB$ and $CDC$ are distinct 3-digit numbers satisfying the equation $CDC - ABB = 25$. Additionally, the digits A, B, C, and D must all be distinct. The discussion explores the implications of removing the restriction on the difference between $CDC$ and $ABB$ and questions how many solutions would exist without that condition. Ultimately, the goal is to determine $\sqrt{ABBCDC}$ under the given constraints.
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$\overline{ABB},$ and $\overline{CDC}$
are two 3-digit numbers ,
giving :
(1)$CDC-ABB=25$
(2)$\overline{ABBCDC}$ (6-digit number) is a perfect square
please find :$\sqrt{ABBCDC}$
(here A,B,C,D are distinct)
 
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Hello, Albert!

$ABB,$ and $CDC$ are two 3-digit numbers, such that:

(1) $CDC-ABB\,=\,25$

(2) $\overline{ABBCDC}$ (6-digit number) is a perfect square.

Find: $\sqrt{ABBCDC}$
(where A,B,C,D are distinct digits)
From (1), we have the alphametic: $\;\begin{array}{cccc} & C&D&C \\ -&A&B&B \\ \hline &&2&5\end{array}$

There are only 3 solutions.

$[1]\;\begin{array}{cccc} & 2&0&2 \\ - &1&7&7 \\ \hline &&2&5\end{array}$

$\qquad$But $ABBCDC \,=\,117,\!202$ is not a square.$[2]\;\begin{array}{cccc}&3&1&3 \\ -&2&8&8 \\ \hline && 2&5 \end{array}$

$\qquad$But $ABBCDC \,=\,288,\!313$ is not a square.$[3]\;\begin{array}{cccc}&4&2&4 \\ - & 3&9&9 \\ \hline && 2&5 \end{array}$

$\qquad$And $\sqrt{ABBCDC} \:=\:\sqrt{399,\!424} \;=\;632$
 
soroban said:
Hello, Albert!
From (1), we have the alphametic: $\;\begin{array}{cccc} & C&D&C \\ -&A&B&B \\ \hline &&2&5\end{array}$There are only 3 solutions.$[1]\;\begin{array}{cccc} & 2&0&2 \\ - &1&7&7 \\ \hline &&2&5\end{array}$$\qquad$But $ABBCDC \,=\,117,\!202$ is not a square.$[2]\;\begin{array}{cccc}&3&1&3 \\ -&2&8&8 \\ \hline && 2&5 \end{array}$$\qquad$But $ABBCDC \,=\,288,\!313$ is not a square.$[3]\;\begin{array}{cccc}&4&2&4 \\ - & 3&9&9 \\ \hline && 2&5 \end{array}$$\qquad$And $\sqrt{ABBCDC} \:=\:\sqrt{399,\!424} \;=\;632$
perfect !
 
Albert said:
$\overline{ABB},$ and $\overline{CDC}$
are two 3-digit numbers ,
giving :
(1)$CDC-ABB=25$
(2)$\overline{ABBCDC}$ (6-digit number) is a perfect square
please find :$\sqrt{ABBCDC}$
(here A,B,C,D are distinct)
If restriction (1)CDC-ABB=25 is taken away
how many soluions we can find ?
 
I have been insisting to my statistics students that for probabilities, the rule is the number of significant figures is the number of digits past the leading zeros or leading nines. For example to give 4 significant figures for a probability: 0.000001234 and 0.99999991234 are the correct number of decimal places. That way the complementary probability can also be given to the same significant figures ( 0.999998766 and 0.00000008766 respectively). More generally if you have a value that...

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