document.write( "Question 1155259: Bob is a high school basketball player. He is a 90 % free throw shooter. That
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Algebra.Com's Answer #777839 by Edwin McCravy(20055)\"\" \"About 
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Bob is a high school basketball player. He is a 90 % free throw shooter. That
\n" ); document.write( "means his probability of making a free throw is 0.90. During the season, what is
\n" ); document.write( "the probability that Bob makes his third free throw on his fifth shot?
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document.write( "We first calculate the number of ways he makes exactly 2 free throws on his\r\n" );
document.write( "first 4, which is what he must do first in order to make his third free throw\r\n" );
document.write( "on his fifth shot.  \r\n" );
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document.write( "Of his 1st, 2nd, 3rd and 4th throws, that's 4 throws CHOOSE 2 or 4C2 = 6 ways\r\n" );
document.write( "he can make exactly 2 free throws.  \r\n" );
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document.write( "[They are these 6 ways: YYNN, YNYN, YNNY, NYYN, NYNY, NNYY]\r\n" );
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document.write( "For each of those, to be successful, he must make his fifth shot. So there are\r\n" );
document.write( "the above 5 ways, with a Y on the end of each of them.\r\n" );
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document.write( "[So they are these 6 ways YYNNY, YNYNY, YNNYY, NYYNY, NYNYY, NNYYY]\r\n" );
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document.write( "So the numerator for the probability is 6.\r\n" );
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document.write( "Now we calculate the denominator for the probability, which is the number of\r\n" );
document.write( "possibilities for the 5 shots.\r\n" );
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document.write( "There are 2 ways to choose the outcome of the first throw, Y or N.\r\n" );
document.write( "There are 2 ways to choose the outcome of the second throw, Y or N.\r\n" );
document.write( "There are 2 ways to choose the outcome of the third throw, Y or N.\r\n" );
document.write( "There are 2 ways to choose the outcome of the fourth throw, Y or N.\r\n" );
document.write( "There are 2 ways to choose the outcome of the fifth throw, Y or N.\r\n" );
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document.write( "That's 2∙2∙2∙2∙2 = 25 = 32 ways.\r\n" );
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document.write( "So the probability is 6 ways out of 32 or 6/32 which reduces to 3/16 = 0.1875.\r\n" );
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document.write( "Edwin
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