document.write( "Question 438588: A telephone company claims that less than 20% of all college students use prepaid phone cards. A random sample of 250 students revealed that 41 of them used prepaid phone cards. Test the company's claim at the 0.05 level of significance. \n" ); document.write( "
Algebra.Com's Answer #303280 by stanbon(75887)\"\" \"About 
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A telephone company claims that less than 20% of all college students use prepaid phone cards. A random sample of 250 students revealed that 41 of them used prepaid phone cards. Test the company's claim at the 0.05 level of significance.
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\n" ); document.write( "Ho: p >= 0.20
\n" ); document.write( "Ha: p < 0.20 (claim)
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\n" ); document.write( "P-hat = 41/250 = 0.164
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\n" ); document.write( "test stat: z(0.164) = (0.164-0.20)/sqrt(0.2*0.8/250) = -1.4230
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\n" ); document.write( "p-value = P(z < -1.4230) = 0.7737
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\n" ); document.write( "Since the p-value is greater than 5%, fail to reject Ho.
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\n" ); document.write( "The test supports the claim.
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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