{"id":"cb_question_bank:24709753-58b0-4689-b7bf-2853ad32f70e","source_id":"cb_question_bank","source_item_id":"24709753-58b0-4689-b7bf-2853ad32f70e","external_id":null,"ibn":"022991-DC","question_id":"34847f8a","program":"SAT","module":"math","domain_code":"P","domain":"Advanced Math","skill_code":"P.A.","skill":"Equivalent expressions","difficulty":"H","score_band":6,"answer_type":"mcq","answer_source":"key","layout_warning":null,"form_id":null,"module_number":null,"position":null,"stem":"The equation above is true for all x greater than 2 , where r and t are positive constants. What is the value of rt ?","stimulus":"the fraction with numerator 2, and denominator x minus 2, end fraction, plus, the fraction with numerator 3, and denominator x plus 5, end fraction, equals, the fraction with numerator r x plus t, and denominator, open parenthesis, x minus 2, close parenthesis, times, open parenthesis, x plus 5, close parenthesis, end fraction","stimulus_html":"<div class=\"stimulus_reference \">\n        <p class=\"standalone_statement style:1 \">\n          <span class=\"math_expression \">\n            <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/690e2f9f0189274c9a71893a2501ffde9f111a6ffa31c181e98028f856ac0a3b\" alt=\"the fraction with numerator 2, and denominator x minus 2, end fraction, plus, the fraction with numerator 3, and denominator x plus 5, end fraction, equals, the fraction with numerator r x plus t, and denominator, open parenthesis, x minus 2, close parenthesis, times, open parenthesis, x plus 5, close parenthesis, end fraction\"></span></span>\n        </p>\n      </div>\n","stem_html":"<p class=\"stem_paragraph \">The equation above is true for all <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/aa24e46b4482ee53721517097d1dd67c605b91461ff6f69085624f878333366b\" alt=\"x greater than 2\"></span>, where <span class=\"italic\">r</span> and <span class=\"italic\">t</span> are positive constants. What is the value of <span class=\"italic\">rt</span> ?</p>\n","rationale_html":"<p>Choice C is correct. To express the sum of the two rational expressions on the left-hand side of the equation as the single rational expression on the right-hand side of the equation, the expressions on the left-hand side must have the same denominator. Multiplying the first expression by <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/8f92ada2448d8c819d3e010eda07b031fcb17f5b691468d6af1a8981c0927731\" alt=\"the fraction with numerator x plus 5, and denominator x minus 5, end fraction \"></span> results in <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/35f5cb12ef8f9010e52c89477bd97409759923130a0a74e890345e47ca6b128f\" alt=\"the fraction with numerator 2 times, open parenthesis, x plus 5, close parenthesis, and denominator, open parenthesis, x minus 2, close parenthesis, times, open parenthesis, x plus 5, close parenthesis, end fraction\"></span>, and multiplying the second expression by <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/b9160ff4f488a93ddd443236a9940bfb39c5d4d24ed417ea77b8c1296705e99f\" alt=\"the fraction with numerator x minus 2, and denominator x minus 2, end fraction\"></span> results in <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/6d0760dcac3d9ae8663e004961c9031184f3b377f5698fd86dcf85a8f0899815\" alt=\"the fraction with numerator 3 times, open parenthesis, x minus 2, close parenthesis, and denominator, open parenthesis, x minus 2, close parenthesis, times, open parenthesis, x plus 5, close parenthesis, end fraction\"></span>, so the given equation can be rewritten as <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/bb725f7ce94eede839bda24fe51195adb303788e05ebf3eb3539819e974ed830\" alt=\"the fraction with numerator 2 times, open parenthesis, x plus 5, close parenthesis, and denominator, open parenthesis, x minus 2, close parenthesis, times, open parenthesis, x plus 5, close parenthesis, end fraction, plus, the fraction with numerator 3 times, open parenthesis, x minus 2, close parenthesis, and denominator, open parenthesis, x minus 2, close parenthesis, times, open parenthesis, x plus 5, close parenthesis, end fraction, equals, the fraction with numerator r x plus t, and denominator, open parenthesis, x minus 2, close parenthesis, times, open parenthesis, x plus 5, close parenthesis, end fraction\"></span>, or <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/80a061b3bdb309180ad7cb4bf98d4b58effdd8d65930a4ffc06605f820a38ff4\" alt=\"the fraction with numerator 2 x plus 10, and denominator, open parenthesis, x minus 2, close parenthesis, times, open parenthesis, x plus 5, close parenthesis, end fraction, plus, the fraction with numerator 3 x minus 6, and denominator, open parenthesis, x minus 2, close parenthesis, times, open parenthesis, x plus 5, close parenthesis, end fraction, equals, the fraction with numerator r x plus t, and denominator, open parenthesis, x minus 2, close parenthesis, times, open parenthesis, x plus 5, close parenthesis, end fraction\"></span>. Since the two rational expressions on the left-hand side of the equation have the same denominator as the rational expression on the right-hand side of the equation, it follows that <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/e046a399380d9883088b1468cc7b8778d3b3fc526acfa14ba4028c662e17b5e4\" alt=\"open parenthesis, 2 x plus 10, close parenthesis, plus, open parenthesis, 3 x minus 6, close parenthesis, equals, r x plus t\"></span>. Combining like terms on the left-hand side yields <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/0b97cc764a22caa345228cea9b05e687f96d002fc9b851e889513144636dff09\" alt=\"5 x plus 4, equals, r x plus t\"></span>, so it follows that <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/7d9edf1216b7dc201c0c8c83bfe4b08b43ee5bdb3c74d762dd6998ebcd02afd8\" alt=\"r equals 5\"></span> and <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/4ff74885ee6bcf070b5297c1417d823f81f5cab9fb6f5c4a75b125458eff93ca\" alt=\"t equals 4\"></span>. Therefore, the value of <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/0a15be98b5285cab890c920a8e96ab23245b2f4d86c3f048b9d6c276a3e9c74e\" alt=\"r t\"></span> is <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/61ccdd429bfc31deb2e0226ac11e9f110b7be913111e2a0297141f095701d01b\" alt=\"5 times 4, which equals 20\"></span>.</p><p>Choice A is incorrect and may result from an error when determining the sign of either <span class=\"italic\">r</span> or <span class=\"italic\">t</span>. Choice B is incorrect and may result from not distributing the 2 and 3 to their respective terms in <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/bb725f7ce94eede839bda24fe51195adb303788e05ebf3eb3539819e974ed830\" alt=\"the fraction with numerator 2 times, open parenthesis, x plus 5, close parenthesis, and denominator, open parenthesis, x minus 2, close parenthesis, times, open parenthesis, x plus 5, close parenthesis, end fraction, plus, the fraction with numerator 3 times, open parenthesis, x minus 2, close parenthesis, and denominator, open parenthesis, x minus 2, close parenthesis, times, open parenthesis, x plus 5, close parenthesis, end fraction, equals, the fraction with numerator r x plus t, and denominator, open parenthesis, x minus 2, close parenthesis, times, open parenthesis, x plus 5, close parenthesis, end fraction\"></span>. Choice D is incorrect and may result from a calculation error.</p><p></p>\n","correct_answer":["C"],"has_media":true,"has_mathml":false,"has_table":false,"source_created_at":"2023-08-02T20:25:59.618000+00:00","source_updated_at":"2023-08-02T20:25:59.618000+00:00","options":[{"label":"A","content_html":"<span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/9c9ceecdd845d666c89f63289b2057c50b70fc985000b67442aa58f2fad36303\" alt=\"negative 20\"></span>\n","ord":0},{"label":"B","content_html":"<span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/a94338896b7f7978fafc9ea30f0accb9ad88788989f24306e84c00eb9454975f\" alt=\"15\"></span>\n","ord":1},{"label":"C","content_html":"<span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/34c721b4e8652cab76cc3b51b979ad2a5008c7af660ef0501509c921476cec99\" alt=\"20\"></span>\n","ord":2},{"label":"D","content_html":"<span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/dea405a7471ea914f5d9b65bf0c848909d39a69130a28049a3c73c33566cfa10\" alt=\"60\"></span>\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}}