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Question 1156063: The objective of the puzzle is to discover the number given the clues below.
It is a three-digit whole number. Its one digit is the product of its hundreds digit and its tens digit. It's an even number It has one odd digit. Its hundreds digit is 4 less than its ones digit.
Answer by greenestamps(13200)   (Show Source):
You can put this solution on YOUR website!
Undoubtedly the whole problem could be solved using formal algebra... but it would be messy, and a lot of work.
Instead, use logical reasoning to find the answer.
(1) ones digit = product of tens digit and hundreds digit
(2) even
(3) one odd digit
(4) hundreds digit = ones digit -4
Start with the requirement that is the most restrictive -- i.e., that leaves the fewest possibilities. It looks to me as if that is (4).
The possibilities with the hundreds digit 4 less than the ones digit are....
5x1
6x2
7x3
8x4
9x5
Now look at the other constraints. Only 6x2 and 8x4 satisfy the requirement that the number be even.
The requirement that the ones digit be the product of the tens digit and hundreds digit would mean 6x2 has to be 632 and 8x4 would have to be 824.
But of those two, 632 is the only one that has one odd digit.
ANSWER: 632
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