document.write( "Question 451067: Having problems understanding Random Variable, Probability Distribution and Expected Value. Please help.\r
\n" ); document.write( "\n" ); document.write( "Question 1. The annual premium for a $5000 insurance policy against the theft of a painting is $150. If the (empirical) probability that the painting will be stolen during the year is.01, what is your expected return from the insurance company if you take out this insurance?\r
\n" ); document.write( "\n" ); document.write( "Question 2. On three rolls of a single die, you will lose $10 if a 5 turns up at least once, and you will win $7 otherwise. What is the expected value of the game?
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Algebra.Com's Answer #310213 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
Question 1. The annual premium for a $5000 insurance policy against the theft of a painting is $150. If the (empirical) probability that the painting will be stolen during the year is.01, what is your expected return from the insurance company if you take out this insurance?
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\n" ); document.write( "Random \"return to you\" values: 4850, -150
\n" ); document.write( "Corresponding Probabilities::: 0.01 , 0.99
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\n" ); document.write( "Expected \"return to you\" = 0.01*4850 + 0.99*(-150) = -$100.00
\n" ); document.write( "You can expect to lose $100 each year you have the policy.
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\n" ); document.write( "\n" ); document.write( "Question 2. On three rolls of a single die, you will lose $10 if a 5 turns up at least once, and you will win $7 otherwise. What is the expected value of the game?
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\n" ); document.write( "P(at least one 5 in three rolls) = 1 - P(no 5 in three) = 1-(5/6)^3 = 0.4213
\n" ); document.write( "P(other results) = 1-0.4213 = 0.5787
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\n" ); document.write( "Random game values: -10 , +7
\n" ); document.write( "Probabilities: 0.4213 , 0.5787
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\n" ); document.write( "Expected game value: 0.4213*(-10)+0.5787*7 = -0.16 = -16 cents
\n" ); document.write( "You can except to lose 16 cents each time you play the game.
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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