document.write( "Question 929450: A random sample of twelve floor jacks is taken and the variable x represents the weight at which each jack fails under successively heavier loading (called the “failure rate of the jack”) is recorded. The sample mean for the 12 recorded weights was 17.1 with a standard deviation of 5.41 tons. Assuming that the population of failure weights for all such jacks is normally distributed, what is the critical value required to form a 95% confidence interval (see attached graphic) for the mean failure weight for all such jacks?\r
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\n" ); document.write( "\n" ); document.write( " A 1.782
\n" ); document.write( " B 1.796
\n" ); document.write( " C 1.960
\n" ); document.write( " D 2.179
\n" ); document.write( " E 2.201 \n" ); document.write( "

Algebra.Com's Answer #564312 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
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document.write( "Hi
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document.write( "CI	
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document.write( "90%	z =1.645
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document.write( "92%	z = 1.751
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document.write( "95%	z = 1.960
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document.write( "98%	z = 2.326
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document.write( "99%	z = 2.576
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document.write( ".....
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document.write( "z = 1.960
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document.write( "C.
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