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[spoiler]I was able to solve this by why is the equation n(n+1) instead of simply n^2 [/spoiler]
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bblast
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Quant 47-Striving for 50
Verbal 34-Striving for 40
My gmat journey :
https://www.beatthegmat.com/710-bblast-s ... 90735.html
My take on the GMAT RC :
https://www.beatthegmat.com/ways-to-bbla ... 90808.html
How to prepare before your MBA:
https://www.youtube.com/watch?v=upz46D7 ... TWBZF14TKW_
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galaxian
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Coz' we need to add the n peoples too (Mary's n direct friends) along with n^2 people (Friends of friends)..hence
n^2 + n = n(n+1)
When in doubt, always try to put nos like take n = 2 & you will find total 6 people [(n)(n+1)] & not 4 will be there in our case.
n^2 + n = n(n+1)
When in doubt, always try to put nos like take n = 2 & you will find total 6 people [(n)(n+1)] & not 4 will be there in our case.
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cans
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n friends donated 500. then n*n people donated 500 each.
thus total money = 500(n + n*n)
a) we know n*500 = (1/16)*500(n + n*n)
16=1+n
n=15
Sufficient
b) 500*(n+n*n) = 120,000
n(n+1)=240
n=15
Sufficient.
IMO D
thus total money = 500(n + n*n)
a) we know n*500 = (1/16)*500(n + n*n)
16=1+n
n=15
Sufficient
b) 500*(n+n*n) = 120,000
n(n+1)=240
n=15
Sufficient.
IMO D
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Cans!!
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Cans!!
