Question 1189573: The number of 3-digit numbers that can be formed by combining the three first digit numbers, is: A.27 B.18 C.9 D.8
Found 3 solutions by ikleyn, Alan3354, greenestamps:
Answer by ikleyn(52776)   (Show Source):
You can put this solution on YOUR website! .
This problem does not specify if repeating is allowed or not.
So, as printed, posted and presented, this post is soup of words - - - not a Math problem.
The composer of this problem deserves to be ticketed.
What is CLEARLY SEEN from this post, is that
the composer is UNFAMILIAR with this class of problems
and does not know how to formulate them correctly.
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Comment from student: I just  ASSUME its with repetition.
My response : If it is assumed, then it should be DECLARED in the problem.
Otherwise, a reader does not know about your assumptions . . .
Answer by Alan3354(69443)  (Show Source):
Answer by greenestamps(13198)  (Show Source):
You can put this solution on YOUR website!
I am hoping that you have shown the problem exactly as it was given to you -- so that the blame for the atrocious language is not yours....
(1) The problem talks about "the three first digit numbers". That phrase is both grammatically and mathematically unclear. One possible interpretation is that it means the digits 1, 2, and 3. But another possible interpretation -- leading to a different answer -- is that it means the digits 0, 1, and 2. And, since the phrase is unclear, there are of course other possible interpretations.
(2) It is also not clear what the phrase "...formed by combining..." means. Certainly it does not involve "combinations" in the formal mathematical sense; given any three digits, there is only one combination of the three of them.
My first thought on reading the phrase was that "by combining" suggests that order IS important; but other interpretations are equally possible.
(3) Finally, as has already been discussed in this thread, the problem does not make it clear whether or not repetition of digits is allowed.
The basic point of this response is that the objective in writing a math problem should be to give the student practice in using math to solve the problem. The problem should not be written in such a way that the student has to spend a lot of time (quite possibly unsuccessfully) trying to figure out what the question is.
Lastly, since I don't know what the question is asking, I can't help you with finding the answer....
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