{"id":"cb_question_bank:7949ae8d-9dcb-4c8a-9dbd-d38d8a9f05f6","source_id":"cb_question_bank","source_item_id":"7949ae8d-9dcb-4c8a-9dbd-d38d8a9f05f6","external_id":null,"ibn":"07831-DC","question_id":"4ff597db","program":"SAT","module":"math","domain_code":"Q","domain":"Problem-Solving and Data Analysis","skill_code":"Q.C.","skill":"One-variable data: Distributions and measures of center and spread","difficulty":"H","score_band":6,"answer_type":"mcq","answer_source":"key","layout_warning":null,"form_id":null,"module_number":null,"position":null,"stem":"The mean amount of time that the 20 employees of a construction company have worked for the company is 6.7 years. After one of the employees leaves the company, the mean amount of time that the remaining employees have worked for the company is reduced to 6.25 years. How many years did the employee who left the company work for the company?","stimulus":"","stimulus_html":null,"stem_html":"<p class=\"stem_paragraph \">The mean amount of time that the 20&nbsp;employees of a construction company have worked for the company is 6.7&nbsp;years. After one of the employees leaves the company, the mean amount of time that the remaining employees have worked for the company is reduced to 6.25&nbsp;years. How many years did the employee who left the company work for the company?</p>\n","rationale_html":"<p>Choice D is correct. The mean amount of time that the 20 employees worked for the company is 6.7 years. This means that the total number of years all 20 employees worked for the company is (6.7)(20) = 134 years. After the employee left, the mean amount of time that the remaining 19 employees worked for the company is 6.25 years. Therefore, the total number of years all 19 employees worked for the company is (6.25)(19) = 118.75 years. It follows that the number of years that the employee who left had worked for the company is 134 – 118.75 = 15.25 years.</p><p>Choice A is incorrect; this is the change in the mean, which isn’t the same as the amount of time worked by the employee who left. Choice B is incorrect and likely results from&nbsp;making the assumption that there were still 20 employees, rather than 19, at the company after the employee left and then subtracting the original mean of 6.7 from that result. Choice C is incorrect and likely&nbsp;results from making the assumption that there were still 20 employees, rather than 19, at the company after the employee left.</p><p></p>\n","correct_answer":["D"],"has_media":false,"has_mathml":false,"has_table":false,"source_created_at":"2023-08-02T20:25:59.634000+00:00","source_updated_at":"2023-08-02T20:25:59.634000+00:00","options":[{"label":"A","content_html":"<p class=\"choice_paragraph \">0.45</p>\n","ord":0},{"label":"B","content_html":"<p class=\"choice_paragraph \">2.30</p>\n","ord":1},{"label":"C","content_html":"<p class=\"choice_paragraph \">9.00</p>\n","ord":2},{"label":"D","content_html":"<p class=\"choice_paragraph \">15.25</p>\n","ord":3}],"attribution":{"source_id":"cb_question_bank","source_name":"College Board digital SAT question bank (community dump)","rights_holder":"College Board","canonical_url":"https://satsuitequestionbank.collegeboard.org/","retrieved_from":"https://raw.githubusercontent.com/mdn522/sat-question-bank/main/data/cb-digital-questions.json","attribution":"SAT practice questions © College Board, from the official SAT Suite Question Bank. Retrieved via the community dump at github.com/mdn522/sat-question-bank.","disclaimer":"SAT® and PSAT/NMSQT® are trademarks registered by the College Board, which is not affiliated with, does not sponsor, and does not endorse this project.","license":"College Board copyright; source repository carries no licence. Local use only.","redistributable":false,"item_count":2017}}