document.write( "Question 750226: I have zero idea what this question is asking me and could really use some help. Please and thank you.
\n" ); document.write( "Given x is a normal variable with mean u=110 and standard deviation o=12 find
\n" ); document.write( "A. P(x≤120)
\n" ); document.write( "B. P(x≥ 80)
\n" ); document.write( "C. P( 108≤ x≤ 117) \n" ); document.write( "
Algebra.Com's Answer #456460 by stanbon(75887)\"\" \"About 
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Given x is a normal variable with mean u=110 and standard deviation o=12 find
\n" ); document.write( "A. P(x≤120)
\n" ); document.write( "z(120) = (120-110)/12 = 10/12 = 5/6
\n" ); document.write( "P(x <= 120) = P(z < 5/6) = normalcdf(-100,5/6) = 0.7977
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\n" ); document.write( "B. P(x≥ 80)
\n" ); document.write( "z(80) = (80-110)/12 = -30/12 = -5/2
\n" ); document.write( "P(x >= 80) = P(z >= -5/2) = normalcdf(-5/2,100) = 0.9938
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\n" ); document.write( "C. P( 108≤ x≤ 117)
\n" ); document.write( "Find the z-value of 108 and of 117
\n" ); document.write( "Find the probabilility that z lies between those z values:
\n" ); document.write( "P(108<= x <=117) = 0.2863
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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