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Contests
National and Regional Contests
USA Contests
MAA AMC
AMC 8
2015 AMC 8
9
9
Part of
2015 AMC 8
Problems
(1)
Widget Sales
Source: 2015 AMC 8 #9
11/25/2015
On her first day of work, Janabel sold one widget. On day two, she sold three widgets. On day three, she sold five widgets, and on each succeeding day, she sold two more widgets than she had sold on the previous day. How many widgets in total had Janabel sold after working
20
20
20
days?
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39
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40
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210
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400
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401
<span class='latex-bold'>(A) </span>39\qquad<span class='latex-bold'>(B) </span>40\qquad<span class='latex-bold'>(C) </span>210\qquad<span class='latex-bold'>(D) </span>400\qquad <span class='latex-bold'>(E) </span>401
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210
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400
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401
AMC 8
2015 AMC 8