document.write( "Question 1090861: A special rubber ball is dropped from the top of a building 81m high. if after the falling it bounces back to two-thirds of the previous bouncing height, then
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Algebra.Com's Answer #705363 by Edwin McCravy(20056)\"\" \"About 
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A special rubber ball is dropped from the top of a building
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document.write( "It falls 81 meters and hits the ground for the 1st time,\r\n" );
document.write( "so its first upward bounce is two-thirds of 81m or 54m.\r\n" );
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document.write( "a1 = 54, r = 2/3\r\n" );
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document.write( "We use geometric series formula for nth term \r\n" );
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document.write( "an = a1rn-1\r\n" );
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document.write( "a5 = 54(2/3)5-1 = 54(2/3)4 = 54(16/81) = 32/3 m = \"10%262%2F3\" meters.\r\n" );
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what is the total distance it has covered the 6th time it touch the ground?
The ball falls 6 times, but rises only 5 times.\r\n" );
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document.write( "We use the sum formula for geometric series:\r\n" );
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document.write( "\"a%5Bn%5D=%28a%5B1%5D%281-r%5En%29%29%2F%281-r%29\"\r\n" );
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document.write( "For the 6 falls, a1 = 81m, r = 2/3\r\n" );
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document.write( "\"a%5B6%5D=%2881%281-%282%2F3%29%5E6%29%29%2F%281-2%2F3%29=221%262%2F3\" meters\r\n" );
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document.write( "For the 5 rises, a1 = 54m, r = 2/3\r\n" );
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document.write( "\"a%5B5%5D=%2854%281-%282%2F3%29%5E5%29%29%2F%281-2%2F3%29=140%262%2F3\" meters\r\n" );
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document.write( "Total distance covered = total falls + total rises = \"221%262%2F3%2B140%262%2F3=362%261%2F3\" meters.\r\n" );
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document.write( "Edwin
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