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Question from cecille, a parent:

my son have a homework, but i don't understand the question. here's the problem:

choose any three digits that are less than ten.
make all the two digit number you can using those three digits.
add up the two digit numbers you created and divided by the
sum of the original three digits.
record your answer. then do it again with another three digits. write your observation about
the answer.

Hi Cecille,

choose any three digits that are less than ten.

Say 2, 4, 7

make all the two digit number you can using those three digits.

24, 27, 47, 42, 72, 74.

add up the two digit numbers you created

24 + 27 + 47 + 42 + 72 + 74 = 286

and divided by the sum of the original three digits.

I think it should be ``divide IT by the sum ...''
The sum is 2 + 4 + 7 = 13, so I divide 286 by 13

record your answer.

286/13 = 22, with no remainder.

then do it again with another three digits.

Say 1, 3, 4. I get 13, 14, 34, 31, 41, 43,
and their sum is 13 + 14 + 34 + 31 + 41 + 43 = 176
The sum of the three digits is 1 + 3 +4 = 8.
176/8 = 22, with no remainder

write your observation about the answer.

Twice I get the same result: 22 with no remainder.
I wonder if starting with any three digits will always give a result of 22.

Claude

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