MGMAT

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MGMAT

by raju232007 » Wed Oct 01, 2008 11:27 pm
The sum of n consecutive positive integers is 45. What is the value of n?

(1) n is even

(2) n < 9


I found the ans for this one which happens to be E..but i took a lot of time to crack this one.Is there any different approach to solve this ques in a much lesser time..Pls help..
Source: — Data Sufficiency |

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by Saffa » Thu Oct 02, 2008 12:43 am
Can't the answer be A?

1) if n = 2 (i.e. 22+23=45)

if n > 2 , but still even the answer will ALWAYS be even and never be 45 (odd)

So n can only be 2. SUFF

Any comments??

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by reacher » Thu Oct 02, 2008 5:50 am
Saffa wrote:Can't the answer be A?

1) if n = 2 (i.e. 22+23=45)

if n > 2 , but still even the answer will ALWAYS be even and never be 45 (odd)

So n can only be 2. SUFF

Any comments??
There is a clue in statement 2. In fact, n can also be 9 (1+2+3...9) =45. In a way, Statement 2 is expressing that n is not 9.

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by reacher » Thu Oct 02, 2008 5:55 am
reacher wrote:
Saffa wrote:Can't the answer be A?

1) if n = 2 (i.e. 22+23=45)

if n > 2 , but still even the answer will ALWAYS be even and never be 45 (odd)

So n can only be 2. SUFF

Any comments??
There is a clue in statement 2. In fact, n can also be 9 (1+2+3...9) =45. In a way, Statement 2 is expressing that n is not 9.
Since there are multiple possibilities for n (for eg: n=2, as you presented it and n=6 when 05+06+...10, the answer has to be E.