document.write( "Question 406695: The numbers of people waiting in the emergency clinic of a small health care facility were randomly counted thirty-five times. Using the data below and the appropriate formula, set up a 95% confidence interval for the mean number of people waiting in emergency.
\n" ); document.write( "11 12 13 13 14 14 14
\n" ); document.write( "15 17 16 16 17 17 16
\n" ); document.write( "15 15 18 19 16 16 18
\n" ); document.write( "17 17 18 17 16 16 16
\n" ); document.write( "15 9 10 18 14 11 9
\n" ); document.write( "(where x and s are calculated from the sample data, n = 35 and z = 1.96)
\n" ); document.write( "Remember to show all your work and round your final answer to the nearest whole number.\r
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Algebra.Com's Answer #286924 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
Find the mean :\r
\n" ); document.write( "\n" ); document.write( "11 12 13 13 14 14 14........91
\n" ); document.write( "15 17 16 16 17 17 16..........114
\n" ); document.write( "15 15 18 19 16 16 18..........117
\n" ); document.write( "17 17 18 17 16 16 16..........117
\n" ); document.write( "15 9 10 18 14 11 9..................86\r
\n" ); document.write( "\n" ); document.write( "\"%2891%2B114%2B117%2B117%2B86%29%2F35=+525%2F35=15\"......the mean is \"15\" \r
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\n" ); document.write( "\n" ); document.write( "The \"interval+\"is\r
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\n" ); document.write( "\n" ); document.write( "Find the standard deviation of using this formula first:\r
\n" ); document.write( "\n" ); document.write( "subtract the mean individually from each of the numbers in the question and square the result.
\n" ); document.write( "x 11 12 13 13 14 14 14
\n" ); document.write( "(x - x)² 16 9 4 4 1 1 1..........36\r
\n" ); document.write( "\n" ); document.write( "x 15 17 16 16 17 17 16
\n" ); document.write( "(15 - x)² 0 4 1 4 4 4 1.............18\r
\n" ); document.write( "\n" ); document.write( " x 15 15 18 19 16 16 18
\n" ); document.write( "(15 - x)² 0 0 9 16 1 1 9.............36\r
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\n" ); document.write( "\n" ); document.write( "x 17 17 18 17 16 16 16
\n" ); document.write( "(15 - x)² 4 4 9 4 1 1 1..................24\r
\n" ); document.write( "\n" ); document.write( "x 15 9 10 18 14 11 9
\n" ); document.write( "(15 - x)² 0 36 25 9 1 16 36............123
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\n" ); document.write( " 237
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\n" ); document.write( "Now add up these results (this is the 'sigma' in the formula): 237\r
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\n" ); document.write( "\n" ); document.write( "\"lower_case_sigma+=+sqrt%28237%2F34%29\" \r
\n" ); document.write( "\n" ); document.write( "\"lower_case_sigma+=+sqrt%286.9705882352941176470588235294118%29\" \r
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\n" ); document.write( "\n" ); document.write( "\"lower_case_sigma+=+%282.6401871591412071041056987587526%29\"\r
\n" ); document.write( "\n" ); document.write( "the standard deviation is \"%282.6401871591412071041056987587526%29\"
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\n" ); document.write( "\n" ); document.write( "\"x+%2B-zs%2Fsqrt%28n%29\"\r
\n" ); document.write( "\n" ); document.write( "= 15 +-(1.96(2.6401871591412071041056987587526))/sqrt(35)\r
\n" ); document.write( "\n" ); document.write( "= 15 +-( 5.1747668319167659240471695671539)=15+-5.18\r
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\n" ); document.write( "\n" ); document.write( "\"15+%2B5.18+=20.17\"\r
\n" ); document.write( "\n" ); document.write( "\"15+-5.18+=+9.82\"\r
\n" ); document.write( "\n" ); document.write( "So the interval is \"9.82%3Cthe_+interval%3C20.17\"....in average:14.995\r
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