MHB Solve for $\overline{abc}:$ $N=3194$

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The problem involves finding the three-digit number $\overline{abc}$ such that the sum of the permutations $\overline{acb}+\overline{bac}+\overline{bca}+\overline{cab}+\overline{cba}$ equals 3194. The total sum of these permutations is expressed as $222(a+b+c)$, which must be a multiple of 222 and lie between 3194 and 4194. The valid multiples of 222 in this range are 3330, 3552, 3774, and 3996, corresponding to potential values of $\overline{abc}$. The only solution that satisfies both the sum condition and the digit sum condition is $\overline{abc} = 358$, where $3+5+8 = 16$. Thus, the final answer is $\overline{abc} = 358$.
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if $N=\overline{acb}+\overline{bac}+\overline{bca}+\overline{cab}+\overline{cba}=3194$ is the sum of five 3-digit numbers
please find :$\overline{abc}$
(here $\overline{abc}$ is also a 3-digit number)
 
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Albert said:
if $N=\overline{acb}+\overline{bac}+\overline{bca}+\overline{cab}+\overline{cba}=3194$ is the sum of five 3-digit numbers
please find :$\overline{abc}$
(here $\overline{abc}$ is also a 3-digit number)
[sp]The sum of all six numbers is $(100 + 10 + 1)(2a+2b+2c) = 222(a+b+c)$, so it has to be a multiple of $222$. Also, it has to lie between $3194$ and $4194$. The only multiples of $222$ in that range are $$\begin{aligned} 3330\ &= 15\times 222 \text{, corresponding to } \overline{abc} = 3330 - 3194 = 136, \\ 3552\ &= 16\times 222 \text{, corresponding to } \overline{abc} = 3552 - 3194 =358, \\ 3774\ &= 17\times 222 \text{, corresponding to } \overline{abc} = 3774 - 3194 =580, \\ 3996\ &= 18\times 222 \text{, corresponding to } \overline{abc} = 3996 - 3194 = 802. \end{aligned}$$ Also, the sum $a+b+c$ must be equal to the corresponding multiple of $222$. The only case where this occurs is when $\boxed{\overline{abc} = 358} = 16\times 222$, with $3+5+8 = 16$.[/sp]
 
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Opalg said:
[sp]The sum of all six numbers is $(100 + 10 + 1)(2a+2b+2c) = 222(a+b+c)$, so it has to be a multiple of $222$. Also, it has to lie between $3194$ and $4194$. The only multiples of $222$ in that range are $$\begin{aligned} 3330\ &= 15\times 222 \text{, corresponding to } \overline{abc} = 3330 - 3194 = 136, \\ 3552\ &= 16\times 222 \text{, corresponding to } \overline{abc} = 3552 - 3194 =358, \\ 3774\ &= 17\times 222 \text{, corresponding to } \overline{abc} = 3774 - 3194 =580, \\ 3996\ &= 18\times 222 \text{, corresponding to } \overline{abc} = 3996 - 3194 = 136. \end{aligned}$$ Also, the sum $a+b+c$ must be equal to the corresponding multiple of $222$. The only case where this occurs is when $\boxed{\overline{abc} = 358} = 16\times 222$, with $3+5+8 = 16$.[/sp]
very nice solution!
 
Opalg said:
[sp]The sum of all six numbers is $(100 + 10 + 1)(2a+2b+2c) = 222(a+b+c)$, so it has to be a multiple of $222$. Also, it has to lie between $3194$ and $4194$. The only multiples of $222$ in that range are $$\begin{aligned} 3330\ &= 15\times 222 \text{, corresponding to } \overline{abc} = 3330 - 3194 = 136, \\ 3552\ &= 16\times 222 \text{, corresponding to } \overline{abc} = 3552 - 3194 =358, \\ 3774\ &= 17\times 222 \text{, corresponding to } \overline{abc} = 3774 - 3194 =580, \\ 3996\ &= 18\times 222 \text{, corresponding to } \overline{abc} = 3996 - 3194 = 802. \end{aligned}$$ Also, the sum $a+b+c$ must be equal to the corresponding multiple of $222$. The only case where this occurs is when $\boxed{\overline{abc} = 358} = 16\times 222$, with $3+5+8 = 16$.[/sp]

almost same method solved at

 
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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