SOLUTION: A contractor who does not meet the deadline on the construction of a building is fined $40,000 per day for each of the first ten days of extra time, and for each additional day the

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Question 1119632: A contractor who does not meet the deadline on the construction of a building is fined $40,000 per day for each of the first ten days of extra time, and for each additional day thereafter the fine is increased by $8,000. If the contractor is fined $1,008,000, by how many extra days was the construction delayed?
Answer by josgarithmetic(39623) About Me  (Show Source):
You can put this solution on YOUR website!
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A contractor who does not meet the deadline on the construction of a building is fined $40,000 per day for each of the first ten days of extra time, and for each additional day thereafter the fine is increased by $8,000. If the contractor is fined $1,008,000, by how many extra days was the construction delayed?
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1008000-400000
608000
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The increase after first ten days is ambiguous. Could be a sequence.
ADDITIONAL DAYS       FINE
1                     48000
2                     54000
3                     62000
4                     70000
5                     78000
6                     86000     ------398000
7                     94000
8                    102000     -------594000
9                    110000



The extra days, some unknown n, which lead up to fines of 608000 dollars.

Sum from 48000 to 8000(n-1) is $608000.

%28n%2F2%29%2848000%2B48000%2B%28n-1%29%2A8000%29=608000------summation formula;
Algebra steps lead to ,...
...
8n%5E2%2B88n-1216=0
n%5E2%2B11n-152=0
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highlight_green%28%28n-8%29%28n%2B19%29=0%29


The solution looks like highlight_green%28n=8%29 days extra after the first ten.