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qid 423 · business

Question: The price of a barrel of crude oil stands at $2 per barrel for a whole month. North Sea Wells is trying to decide how many barrels of oil a day it should extract to maximize profits. The cost of extracting x barrels of oil a day is C(x) = [{x^2} / {10,000}] + 500, where C(x) is in dollars. How many barrels of oil a day will maximize profits?

  1. 12,500 barrels a day
  2. 7,500 barrels a day
  3. 30,000 barrels a day
  4. 15,000 barrels a day
  5. 10,000 barrels a day
  6. 20,000 barrels a day
  7. 2,500 barrels a day
  8. 5,000 barrels a day
  9. 25,000 barrels a day
  10. 17,500 barrels a day

Our answer: E. 10,000 barrels a day Source weak

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How it was answered

Multi-step solver (maze), replayed by code

card: maze · card sha256 bfb81f9de9c16911…

Current source

https://openstax.org/books/calculus-volume-1/pages/4-7-applied-optimization-problems

Source weak (http_get_200_text_and_question_terms)

retrieved 2026-09-17T23:25:47.172Z

page text sha256 2c77be89c4cad47e… · content sha256 —

addendum maze_qid423_b4_maze_input_ADDENDUM_source_bf20260917T232547Z · sha256 57826e002731e741… · replaces the version below, addendum sha256 d24c1bb4b53cd591…

Earlier version (superseded)

No public source has been found for this card yet (3 places checked internally).

addendum maze_qid423_b4_maze_input_ADDENDUM_source · sha256 d24c1bb4b53cd591…

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