Princeton GMAT Math Bible-----------Remaider questions

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I took the test on Nov.,2008.I encountered a few remaider questions
that are very similiar to the questions on Princeton GMAT Math Bible.

anybody can explain the following question for me? many thanx.



1. The reminder of x divided by 9, 15 or 21 is 3. If x is an integer, what is the smallest possible value of x?


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by cramya » Mon Dec 15, 2008 10:19 pm
Not sure if I missed any trick here.

I think x=3 would satisfy the least integer part unless I missed something.

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1. The reminder of x divided by 9, 15 or 21 is 3. If x is an integer, what is the smallest possible value of x?


Ans: The sequence for such type of numbers will be
= N [ LCM (9, 15, 21 )] + 3 , where N is any whole number
When we will put N = 0, we will have ;least exited number which is 3 but when we put N = 1 we will have the answer required answer as
Number = 1 x 315 + 3 = 318
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amyyoung999 wrote:I took the test on Nov.,2008.I encountered a few remaider questions
that are very similiar to the questions on Princeton GMAT Math Bible.

anybody can explain the following question for me? many thanx.



1. The reminder of x divided by 9, 15 or 21 is 3. If x is an integer, what is the smallest possible value of x?


Amy
The approach in the post above does let you find all such values of x, but as cramya points out, there's no reason why x cannot be equal to 3 here. Indeed, x could also be negative, and there is no smallest possible value, so either there was some additional restriction in the question or the question is badly designed.
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