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M is a certain set of numbers with an average (arithmetic
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17 Jul 2014, 06:02
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69% (01:59) correct 31% (01:57) wrong based on 233 sessions
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M is a certain set of numbers with an average (arithmetic mean) of 10 and a standard deviation of 2.5. Q is a subset of M consisting of 5 terms. Exactly 80% of the numbers in Q are located within 2 standard deviations from the average of M. Which of the following could Q be? A. {3, 4, 5, 10, 14} B. {3, 6, 7, 10, 12} C. {3, 5, 5, 10, 16} D. {1, 5, 7, 10, 18} E. {5, 6, 7, 10, 12}
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M is a certain set of numbers with an average (arithmetic
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17 Jul 2014, 06:16
goodyear2013 wrote: M is a certain set of numbers with an average (arithmetic mean) of 10 and a standard deviation of 2.5. Q is a subset of M consisting of 5 terms. Exactly 80% of the numbers in Q are located within 2 standard deviations from the average of M. Which of the following could Q be?
A. {3, 4, 5, 10, 14} B. {3, 6, 7, 10, 12} C. {3, 5, 5, 10, 16} D. {1, 5, 7, 10, 18} E. {5, 6, 7, 10, 12} Exactly 80% of the numbers in Q, so 4 out of 5 numbers are from 10  2*{SD} = 5 to 10 + 2*{SD} = 15. A. {3, 4, 5, 10, 14} > only 3 numbers are in this range. Discard. B. {3, 6, 7, 10, 12} > 4 numbers are in this range. OK. C. {3, 5, 5, 10, 16} > only 3 numbers are in this range. Discard. D. {1, 5, 7, 10, 18} > only 3 numbers are in this range. Discard. E. { 5, 6, 7, 10, 12} > all 5 numbers are in this range. Discard. Answer: B. Similar questions to practice: themeanandthestandarddeviationofthe8numbersshown98248.htmlthestandarddeviationofanormaldistributionofdatais99221.htmlavendingmachineisdesignedtodispense8ouncesofcoffee93351.htmlarithmeticmeanandstandarddeviationofacertainnormal104117.htmlthelifetimeofallthebatteriesproducedbyacertaincomp101472.html7075808590105105130130130thelistshownconsistof100361.htmlforacertainexamascoreof58was2standarddeviationsb128661.htmlacertaincharacteristicinalargepopulationhasa143982.htmltheresidentsoftownxparticipatedinasurvey83362.htmlthestandarddeviationofanormaldistributionofdatais99221.htmlthemeanandthestandarddeviationofthe8numbersshown98248.htmlifacertainsampleofdatahasameanof200anda127810.htmlgiventhatthemeanofsetais10whatistherangeoftwo141964.htmlifacertainsampleofdatahasameanof240andthevalue171843.htmlforacertainexamascoreof58was2standarddeviationsb128661.htmlCheck other Standard Deviation Questions in our Special Questions Directory. Hope this helps.
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Re: M is a certain set of numbers with an average (arithmetic
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30 Oct 2018, 06:11
10  2*{SD} = 5 to 10 + 2*{SD} = 15
please explain this .
Thanks




Re: M is a certain set of numbers with an average (arithmetic
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30 Oct 2018, 06:11






