Answer:
$9,889.82
Step-by-step explanation:
Nominally, Cynthia paid ...
2000·$35.49 = $70,980
With the broker's commission of 8.8%, she actually paid ...
$70,980·1.088 = $77,226.24
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When Cynthia sold, she nominally received ...
600·$48.57 +1150·$46.10 +250·$53.46
= $29,142 +53,015 +13,365 = $95,522
Because of the broker's 8.8% commission, she actually received ...
$95,522·0.912 = $87,116.06
Cynthia's total profit was ...
$87,116.06 -77,226.24 = $9,889.82
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The broker made $14,652.18 on Cynthia's transactions, almost half again as much as Cynthia made.