document.write( "Question 549504: After tossing some coins, it is observed that the probability of obtaining 10 heads
\n" ); document.write( "and 15 tails is the same as the probability of obtaining 15 heads and 10 tails. Find
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Algebra.Com's Answer #357819 by stanbon(75887)\"\" \"About 
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After tossing some coins, it is observed that the probability of obtaining 10 heads and 15 tails
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\n" ); document.write( "P(10 h and 15 t) = nC10(1/2)^n
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\n" ); document.write( "P(15 h and 10 t) = nC15(1/2)^n
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\n" ); document.write( "nC10 = nC15
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\n" ); document.write( "n!/(n-15)!*15! = n!/(n-10)!*10!
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\n" ); document.write( "(n-15)!*15! = (n-10)!*10!
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\n" ); document.write( "(n-15)!*15*14*13*12*11 = (n-10)!
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\n" ); document.write( "15*14*13*12*11 = (n-10)(n-11)(n-12)(n-13)(n-14)
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\n" ); document.write( "So n-10 = 15
\n" ); document.write( "n = 25
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