document.write( "Question 1200576: The highway fuel economy of a 2016 Lexus RX 350 FWD 6-cylinder 3.5-L automatic 5-speed using premium fuel is a normally distributed random variable with a mean of μ = 25.50 mpg and a standard deviation of σ = 2.25 mpg.
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\n" ); document.write( "(b) Within what interval would you expect the sample mean to fall, with 98 percent probability? (Round your answers to 4 decimal places.) \n" ); document.write( "
Algebra.Com's Answer #834744 by Theo(13342)\"\" \"About 
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mean is 25.5 mpg
\n" ); document.write( "standard deviation is 2.25 mpg
\n" ); document.write( "critical z-score for 98% probability = plus or minus z = 2.326347877.
\n" ); document.write( "z = (x - m) / s
\n" ); document.write( "z is the z-score
\n" ); document.write( "x is the raw score
\n" ); document.write( "m is the poulation mean
\n" ); document.write( "s is the population standard deviation
\n" ); document.write( "to solve for x, the formula becomes:
\n" ); document.write( "x = z * s + m
\n" ); document.write( "when z = 2.326347877 and m = 25.5 and s = 2.25, the formula becomes:
\n" ); document.write( "x = -2.326347877 * 2.25 + 25.5 = 20.26571728 on the low side.
\n" ); document.write( "x = 2.326347877 * 2.25 + 25.5 = 30.734202672 on the high side.
\n" ); document.write( "rounds as required.
\n" ); document.write( "this is what it looks like, using the calculator at https://davidmlane.com/hyperstat/z_table.html
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