document.write( "Question 1143688: A student doing an internship at a large research firm collected the following data, representing all of the studies the firm had conducted over the past 3 years.
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\n" ); document.write( "What is the probability that the study did not use randomization, if we already know that the study was a retrospective observational study?
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\n" ); document.write( "Randomization? Retrospective Observational Prospective Observational Experiment Total
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\n" ); document.write( "No 53 62 115 230
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\n" ); document.write( "0.88
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\n" ); document.write( "0.27 \n" ); document.write( "
Algebra.Com's Answer #764574 by ikleyn(52909)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "A student doing an internship at a large research firm collected the following data, representing all of the studies
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\n" ); document.write( "What is the probability that the study did not use randomization, if we already know that the study was
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document.write( "Randomization?	Retrospective Observational	Prospective Observational	Experiment	Total\r\n" );
document.write( "Yes	         7	                        28	                         35	          70\r\n" );
document.write( "No	        53	                        62	                        115	         230\r\n" );
document.write( "Total	        60	                        90	                        150	         300\r\n" );
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document.write( "Answer options\r\n" );
document.write( "0.88\r\n" );
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document.write( "0.85\r\n" );
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document.write( "0.27\r\n" );
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\n" ); document.write( "\n" ); document.write( "            What you see above -- is your post.\r
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\n" ); document.write( "\n" ); document.write( "            Please pay attention on   how  I  EDITED  (formatted)  it   TO  MAKE  SENSE.\r
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document.write( "ANSWER.    P = \"53%2F60\" = 0.88  (correct with 2 decimal places)\r\n" );
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document.write( "Although the formula is SELF-EXPLANATORY, I will give some explanation.\r\n" );
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document.write( "    Go to the column \"Retrospective Observational\", take there two appropriate numbers \"53\" and \"60\" and make a ratio.\r\n" );
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