gwd-1-11

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Q11:

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 ATH extrusionok="f" gradientshapeok="t" connecttype="rect">ATH>of the total amount donated.

(2) The total amount donated was $120,000.

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my line is this:

1.500n=1/16(500n+500n^2),n=15

2.500n+500n^2=120000,n=15

so the right answer is d,is it right?

himba

条件（1）

N可以是0。