{"id":"cb_question_bank:c49f47ba-1a9a-4fd1-9bd3-28195e8f2186","source_id":"cb_question_bank","source_item_id":"c49f47ba-1a9a-4fd1-9bd3-28195e8f2186","external_id":null,"ibn":"026242-DC","question_id":"9eb896c5","program":"SAT","module":"math","domain_code":"Q","domain":"Problem-Solving and Data Analysis","skill_code":"Q.D.","skill":"Two-variable data: Models and scatterplots","difficulty":"M","score_band":5,"answer_type":"mcq","answer_source":"key","layout_warning":null,"form_id":null,"module_number":null,"position":null,"stem":"Which of the following could be the equation for a line of best fit for the data shown in the scatterplot above?","stimulus":"The figure presents a scatterplot in the first quadrant of the x y plane. The numbers 0 through 10, in increments of 2, are indicated on the x axis. The numbers 0 through 30, in increments of 5, are indicated on the y axis. There are 8 data points in the scatterplot. The data points begin at the point with approximate coordinates 1 comma 4, and trend upward and to the right until they end at the point with approximate coordinates 8 comma 26.","stimulus_html":"<div class=\"stimulus_reference \">\n        <div class=\"passage \">\n          <div class=\"prose style:1 \">\n            <div class=\"standalone_image \">\n              <img src=\"/api/assets/0a8a114667bd57151b85e703d60118b6fa4684135b535da245170e0cb8e547c5\" alt=\"The figure presents a scatterplot in the first quadrant of the x y plane. The numbers 0 through 10, in increments of 2, are indicated on the x axis. The numbers 0 through 30, in increments of 5, are indicated on the y axis. There are 8 data points in the scatterplot. The data points begin at the point with approximate coordinates 1 comma 4, and trend upward and to the right until they end at the point with approximate coordinates 8 comma 26.\" width=\"178\" height=\"132\"></div>\n          </div>\n        </div>\n      </div>\n","stem_html":"<p class=\"stem_paragraph \">Which of the following could be the equation for a line of best fit for the data shown in the scatterplot above?</p>\n","rationale_html":"<p>Choice A is correct. The data show a strong linear relationship between <span class=\"italic\">x</span> and <span class=\"italic\">y</span>. The line of best fit for a set of data is a linear equation that minimizes the distances from the data points to the line. An equation for the line of best fit can be written in slope-intercept form, <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/39dda01984e771026b6a8a741d3ebb66f1a29f1e81583b67f8d50f6e2dbb783e\" alt=\"y equals, m x plus b\"></span>, where <span class=\"italic\">m</span> is the slope of the graph of the line and <span class=\"italic\">b</span> is the <span class=\"italic\">y</span>-coordinate of the <span class=\"italic\">y</span>-intercept of the graph. Since, for the data shown, the <span class=\"italic\">y</span>-values increase as the <span class=\"italic\">x</span>-values increase, the slope of a line of best fit must be positive. The data shown lie almost in a line, so the slope can be roughly estimated using the formula for slope, <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/d90665e9527746054088c372f023f7eaa687ac5da59918408884c2d405e79dcc\" alt=\"m equals, the fraction with numerator y sub 2 minus y sub 1, and denominator x sub 2 minus x sub 1, end fraction\"></span>. The leftmost and rightmost data points have coordinates of about <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/88ef5da5e9d8f4ea8545894c47eaff251bbdbb451e1ea22cf520a25cea44d303\" alt=\"1 comma 4\"></span> and <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/b7b1ffb8e058fa0812f4da4ccdbd98dd3d11c740d3568698aec401592c82668a\" alt=\"8 comma 26\"></span>, so the slope is approximately <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/ab4ba4ba95532512118344213560161e6c2ca54f1b047026f658ba60e0e18a14\" alt=\"the fraction with numerator 26 minus 4, and denominator 8 minus 1, end fraction, equals the fraction 22 over 7\"></span>, which is a little greater than 3. Extension of the line to the left would intersect the <span class=\"italic\">y</span>-axis at about <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/6f3a9226f302010cb970c4c9a7ec50c741c7d5a2c55111fb791bcf92be5e5159\" alt=\"the point with coordinates 0 comma 1\"></span>. Only choice A represents a line with a slope close to 3 and a <span class=\"italic\">y</span>-intercept close to <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/6f3a9226f302010cb970c4c9a7ec50c741c7d5a2c55111fb791bcf92be5e5159\" alt=\"the point with coordinates 0 comma 1\"></span>.</p><p>Choice B is incorrect and may result from switching the slope and <span class=\"italic\">y</span>-intercept. The line with a <span class=\"italic\">y</span>-intercept of <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/18ef80b67575a6bd348af21c284b6114c5668aad7ed5c2b152bdc5ba431a094d\" alt=\"0 comma 3 \"></span> and a slope of 0.8 is farther from the data points than the line with a slope of 3 and a <span class=\"italic\">y</span>-intercept of <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/61192f675e33f64e740ddb8fe537ff78347ac6bb1abc7bde5e8516a57fe66ab2\" alt=\"0 comma 0 point 8\"></span>. Choices C and D are incorrect. They represent lines with negative slopes, not positive slopes.</p><p></p>\n","correct_answer":["A"],"has_media":true,"has_mathml":false,"has_table":false,"source_created_at":"2023-08-02T20:25:59.620000+00:00","source_updated_at":"2023-08-02T20:25:59.620000+00:00","options":[{"label":"A","content_html":"<p class=\"choice_paragraph \">\n            <span class=\"math_expression \">\n              <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/b48a020dfac561130f1127500de2cb1f996195f7340668751456ca8c4695abd4\" alt=\"y equals, 3 x plus 0 point 8\"></span></span>\n          </p>\n","ord":0},{"label":"B","content_html":"<p class=\"choice_paragraph \">\n            <span class=\"math_expression \">\n              <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/7b2e057202fff296f12279cfa209cfa2232b80ed4c9b6e0ac6f95cebe1bcdf79\" alt=\"y equals, 0 point 8 x, plus 3\"></span></span>\n          </p>\n","ord":1},{"label":"C","content_html":"<p class=\"choice_paragraph \">\n            <span class=\"math_expression \">\n              <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/626c7d58aec304ec4095c07d3d37af9eb3e5643967d6b68cea8b4f531457651e\" alt=\"y equals, negative 0 point 8 x, plus 3\"></span></span>\n          </p>\n","ord":2},{"label":"D","content_html":"<p class=\"choice_paragraph \">\n            <span class=\"math_expression \">\n              <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/b770813b8850cc71336e93d5b36b8394f879a96750d8acda47ac1fc03977427f\" alt=\"y equals, negative 3 x plus 0 point 8\"></span></span>\n          </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}}