document.write( "Question 1147643: A manufacturer knows that their items have a normally distributed lifespan, with a mean of 3.3 years, and standard deviation of 0.5 years.The 7% of items with the shortest lifespan will last less than how many years? \n" ); document.write( "

Algebra.Com's Answer #768991 by rothauserc(4718) $\"\"$ $\"About$

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The z-score associated with a probability of 0.07 is -1.47
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\n" ); document.write( "Note use table of z-scores to lookup probabilities
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\n" ); document.write( "(X - 3.3)/0.5 = -1.47
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\n" ); document.write( "X - 3.3 = −0.735
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\n" ); document.write( "X = 2.565 is approximately 3
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\n" ); document.write( "Therefore, we can expect 3 items have shortest lifespan represent 7% of all items
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