document.write( "Question 297867: A bag contains 3 nickels, 4 dimes, and 5 quarters. If two coins are selected at random without replacing the first one selected, what is the probability that the two coins match? \n" ); document.write( "
Algebra.Com's Answer #214454 by Fombitz(32388)![]() ![]() You can put this solution on YOUR website! 3 nickels \n" ); document.write( "4 dimes \n" ); document.write( "5 quarters \n" ); document.write( "12 total coins \n" ); document.write( "P(N)=3/12 \n" ); document.write( "P(D)=4/12 \n" ); document.write( "P(Q)=5/12 \n" ); document.write( "Once one coin is chosen then the total number of coins drops to 11 and the probability of each coin is adjusted. \n" ); document.write( "P(N if nickel is chosen first)=2/11 \n" ); document.write( "P(D if dime is chosen first)=3/11 \n" ); document.write( "P(Q if quarter is chosen first)=4/11 \n" ); document.write( "Since each event is independent, multiply the probabilities. \n" ); document.write( "P(nickel then nickel)=(3/12)(2/11)=1/22 \n" ); document.write( "P(dime then dime)=(4/12)(3/11)=1/11 \n" ); document.write( "P(quarter then quarter)=(5/12)(4/11)=5/33 \n" ); document.write( " |