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)
 
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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