document.write( "Question 1119062: A physical fitness association is including the mile run in its​ secondary-school fitness test. The time for this event for boys in secondary school is known to possess a normal distribution with a mean of 450450 seconds and a standard deviation of 6060 seconds. Between what times do we expect most​ (approximately 95%) of the boys to run the​ mile? \n" ); document.write( "
Algebra.Com's Answer #734514 by Boreal(15235)\"\" \"About 
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95% would be a z between -1.96 and +1.96
\n" ); document.write( "z=(x-mean)/sd
\n" ); document.write( "1.96=(x-450)/60
\n" ); document.write( "117.6=x-450
\n" ); document.write( "x=567.6 seconds one end and 332.4 seconds other end.
\n" ); document.write( "(332.4, 567.6) units are seconds.
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