Find a three-digit number containing three different digits

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Discussion Overview

The discussion revolves around finding a three-digit number composed of three different digits that satisfies specific conditions related to perfect squares. The conditions include the sum of the first digit and the number formed by the second and third digits, the product of the first digit and the number formed by the second and third digits, and the sum of all three digits.

Discussion Character

  • Exploratory, Mathematical reasoning, Debate/contested

Main Points Raised

  • One participant proposes the number 036, arguing that it meets the conditions since 0 + 3 + 6 = 9, 0 + 36 = 36, and 0 x 36 = 0, while questioning whether zero is considered a perfect square.
  • Another participant suggests the number 081 as another potential solution, contingent on the same assumption about zero.
  • A different participant presents the number 916 without further explanation or justification.
  • One participant elaborates on their mathematical reasoning, indicating that the sum of the digits must fall within a specific range and identifying the perfect squares within that range, specifically noting that only certain sums (4, 9, 16, 25) can be achieved with three digits.
  • This participant expresses uncertainty about the number of combinations that yield a sum of 25, suggesting that there may be fewer than four possibilities.
  • A new participant expresses interest in the topic and offers to share challenging questions for further discussion.

Areas of Agreement / Disagreement

Participants express differing views on whether zero should be considered a perfect square, leading to multiple competing solutions. The discussion remains unresolved regarding the validity of the proposed numbers and the conditions set forth.

Contextual Notes

There are limitations regarding the assumptions about perfect squares, particularly concerning the inclusion of zero, and the mathematical steps leading to the identification of valid three-digit numbers are not fully resolved.

Who May Find This Useful

Individuals interested in mathematical puzzles, number theory, or brain teasers may find this discussion engaging.

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Find a three-digit number containing three different digits where the following are all perfect squares:

(A) The sum of the first digit and the number formed by the second and third digits;
(B) The first digit multiplied by the number formed by the second and third digits and
(C) The sum of the three digits.
 
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In the midst of figuring this out I found out that I need to know if you consider zero a perfect square - some people do.

Assuming that you do my answer is

036

0 + 3 + 6 = 9
0 + 36 = 36
0 x 36 = 0


also "081"

If not, I am still finishing up all the possible ones without zeros...
 
916
 
A little bit about the math method I used, being a freakin' genius!

First off - assess which requirement narrows the answers down. It's the last one.

Any such X Y Z numbers must be at least one, and at greatest nine.

So at least 1 + 1 + 1
and at greatest 9 + 9 + 9

3 to 27

There are only 4 PS in that range:

4 - 9 - 16 - 25

So the only possible XYZ number is numbers that add up to those.

4 can easily be done with only a few variables. Nine takes a bit more...


4 and nine both have no such answers needed.

So on to 16, which has just the one I mentioned.

How many does 25 have? I didn't bother once I finally got one - but maybe greg knows!

My guess is less than 4!
 
Hey Greg - I am new here and like this brain teaser thing.

I was wondering - I could provide some very difficult questions, ones that no one could find the answer to online, and would truly require some brain "teasing". Just PM me or something if you'd like to view any of them, thanks!
 

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