value of n - please help

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value of n - please help

by rjanardhanan » Wed Dec 28, 2011 8:02 pm
Mary persuaded n friends to donate $500 each to her election campaign, and then each of these n friends persuaded n more people to donate $500 each to Mary's campaign. If no one donated more than once and if there were no other donations, what was the value of n?
(1) The first n people donated 1/16 of the total amount donated.
(2) The total amount donated was $120,000.
A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D. EACH statement ALONE is sufficient.
E. Statements (1) and (2) TOGETHER are NOT sufficient.
Last edited by rjanardhanan on Wed Dec 28, 2011 8:26 pm, edited 1 time in total.
Source: — Data Sufficiency |

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by pemdas » Wed Dec 28, 2011 8:12 pm
Please correct st(1) condition: The first n people donated 1/16 of the total amount donated.

total donations = 500n + 500n^2
st(1) 16(500n)= 500n+500n^2 Suff
st(2) 500n + 500n^2 = 120,000 Suff

d
rjanardhanan wrote:Mary persuaded n friends to donate $500 each to her election campaign, and then each of these n friends persuaded n more people to donate $500 each to Mary's campaign. If no one donated more than once and if there were no other donations, what was the value of n?
(1) The first n people donated 161 of the total amount donated.
(2) The total amount donated was $120,000.
A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D. EACH statement ALONE is sufficient.
E. Statements (1) and (2) TOGETHER are NOT sufficient.
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