MHB *Find the Number Satisfying the Given Conditions

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The problem involves finding a two-digit number where the sum of its digits equals 12 and the number is 13 times the tens digit. By defining the tens digit as A and the units digit as B, the equations A + B = 12 and B = 3A are established. Substituting B into the first equation leads to A = 3 and B = 9, resulting in the number 39. The solution confirms that the conditions are satisfied, demonstrating the problem's simplicity.
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The sum of the digits of a two-digit number is $12$ The number is $13$ times the tens digit. Find the number

well from $3+9=12$ we can see that the number would be $39$ which is $3\times 13$

but again I had trouble knowing how to set this up

In that $10t+u=12$ how do you set up $13t=$

mahalo much...
 
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I would let A be the ten's digit and B be the one's digit. We are then told:

(1) $\displaystyle A+B=12$

$\displaystyle 10A+B=13A$ or:

(2) $\displaystyle B=3A$

Now substitute for B into (1) using (2) to solve for A, then from (2) you will have B.

What number do you find?
 
does it really have to be this easy...

A=3 then B=9

Oh and yes, Honolulu is a very nice place to live, me 12 years +
 
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Yes, it is just that easy! (Handshake)
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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