GMATprep

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GMATprep

by veekay » Mon Oct 15, 2007 8:43 pm
Can anyone provide a better approach to solve this one? I almost took 5 minutes to solve this
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by Bharat » Mon Oct 15, 2007 11:39 pm
Given series is an A.P.
for any AP; Tn = T1 + (n-1)d
here d = -3
T1 = 23
& Tn = -4

On solving: n = 10

I believet that this is the fastest solution, however, I am eager to know if there is a still faster approach.

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by veekay » Tue Oct 16, 2007 7:24 am
Bharat wrote:Given series is an A.P.
for any AP; Tn = T1 + (n-1)d
here d = -3
T1 = 23
& Tn = -4

On solving: n = 10

I believet that this is the fastest solution, however, I am eager to know if there is a still faster approach.
Thanks Bharat. I was not interpreting it that way. I thought series first increases from t1 to tn and then decreases to t1 and it sum is 23 :wink:

Not sure how I got the right answer.

This is straigh forward.