【SAT官方每日一题】7/29/12 Mathematics > Standard Multiple Choice

滚吧肥汤圆UID: 3272378

Read the following SAT test question and then click on a button to select your answer.
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4 c2 B& ?- N% X) @) f) FEvery student who studies art in a certain school receives exactly one of the grades A, B, C, or D. If [img=]http://sat.collegeboard.org/mathmlgen/content/question/QOTD/2012/20120729_1.png[/img] of the students receive A’s, [img=]http://sat.collegeboard.org/mathmlgen/content/question/QOTD/2012/20120729_2.png[/img]  receive B’s, [img=]http://sat.collegeboard.org/mathmlgen/content/question/QOTD/2012/20120729_3.png[/img]  receive C’s, and [img=]http://sat.collegeboard.org/mathmlgen/content/question/QOTD/2012/20120729_4.png[/img]  students receive D’s, how many students in the school study art?

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A.  30
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2 P( E% `# I# N% @& B" @+ oB.  60
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2 U! |- W9 _+ Y( {  Q$ Q& ZC.  100

D. 200

E.  500

正确答案:D

5 l- B( H& o" f' w' s7 \解析:
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; B. }% {! k) |& a- b4 M/ `) q$ b' wThe students who receive A’s, B’s, and C’s account for [img=]http://sat.collegeboard.org/mathmlgen/content/question/QOTD/2012/20120729_12.png[/img]  of the students, that is, [img=]http://sat.collegeboard.org/mathmlgen/content/question/QOTD/2012/20120729_13.png[/img] . This leaves[img=]http://sat.collegeboard.org/mathmlgen/content/question/QOTD/2012/20120729_14.png[/img]   of the students receiving D’s. You know that [img=]http://sat.collegeboard.org/mathmlgen/content/question/QOTD/2012/20120729_15.png[/img]  students receive D’s, so [img=]http://sat.collegeboard.org/mathmlgen/content/question/QOTD/2012/20120729_16.png[/img]  is [img=]http://sat.collegeboard.org/mathmlgen/content/question/QOTD/2012/20120729_17.png[/img]  of the total. This means that the total number of students is[img=]http://sat.collegeboard.org/mathmlgen/content/question/QOTD/2012/20120729_18.png[/img]  times [img=]http://sat.collegeboard.org/mathmlgen/content/question/QOTD/2012/20120729_19.png[/img] , or[img=]http://sat.collegeboard.org/mathmlgen/content/question/QOTD/2012/20120729_20.png[/img]  .
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