document.write( "Question 1203802: A bag contains three coins, one of which has a head on both sides while the other two coins are normal. A coin is chosen at random from the bag and tossed three times. The number of heads is a random variable, say X.
\n" ); document.write( "(a) Find the discrete pdf of X. (Hint: Use the Law of Total Probability with B1 = a normal coin and B2 = two-headed coin.)
\n" ); document.write( "(b) Sketch the discrete pdf and the CDF of X. \n" ); document.write( "
Algebra.Com's Answer #848255 by Edwin McCravy(20067)\"\" \"About 
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document.write( "P(B1,H,H,H) = (1/2)(1/2)(1/2)(1/2) = 1/16, n(H) = 3\r\n" );
document.write( "P(B1,H,H,T) = (1/2)(1/2)(1/2)(1/2) = 1/16, n(H) = 2\r\n" );
document.write( "P(B1,H,T,H) = (1/2)(1/2)(1/2)(1/2) = 1/16, n(H) = 2\r\n" );
document.write( "P(B1,H,T,T) = (1/2)(1/2)(1/2)(1/2) = 1/16, n(H) = 1\r\n" );
document.write( "P(B1,T,H,H) = (1/2)(1/2)(1/2)(1/2) = 1/16, n(H) = 2\r\n" );
document.write( "P(B1,T,H,T) = (1/2)(1/2)(1/2)(1/2) = 1/16, n(H) = 1\r\n" );
document.write( "P(B1,T,T,H) = (1/2)(1/2)(1/2)(1/2) = 1/16, n(H) = 1\r\n" );
document.write( "P(B1,T,T,T) = (1/2)(1/2)(1/2)(1/2) = 1/16, n(H) = 0\r\n" );
document.write( "P(B2,H,H,H) = (1/2)( 1 )( 1 )( 1 ) =  1/2, n(H) = 3\r\n" );
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document.write( "X(0) = P(0) = 1/16     = 1/16\r\n" );
document.write( "X(1) = P(1) = 3/16     = 3/16\r\n" );
document.write( "X(2) = P(2) = 3/16     = 3/16\r\n" );
document.write( "X(3) = P(3) = 1/16+1/2 = 9/16 \r\n" );
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document.write( "           Sum = 16/16 = 1\r\n" );
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document.write( "n |  X \r\n" );
document.write( "0 | 1/16\r\n" );
document.write( "1 | 3/16\r\n" );
document.write( "2 | 3/16\r\n" );
document.write( "3 | 9/16\r\n" );
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document.write( "     \r\n" );
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document.write( "Edwin

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