document.write( "Question 1023644: On average, a proportion of 0.48 newborns are girls. What are the chances that in a family with 4 children there are exactly three daughters. Provide answer as a proportion, rounding to two decimal places \n" ); document.write( "
Algebra.Com's Answer #639280 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
\r\n" );
document.write( "This is a binomial probability problem.\r\n" );
document.write( "\r\n" );
document.write( "The probability that in N trials, there will be\r\n" );
document.write( "exactly x succesful outcomes, if the probability\r\n" );
document.write( "of a success in 1 trial is p, is given by the\r\n" );
document.write( "formula\r\n" );
document.write( "\r\n" );
document.write( "\"NCx%2Ap%5Ex%2A%281-p%29%5E%28N-x%29\"\r\n" );
document.write( "\r\n" );
document.write( "We seek the probability that in 4 trials, there \r\n" );
document.write( "will be exactly 4 succesful outcomes (girls), \r\n" );
document.write( "given that the probability of a success (girl) \r\n" );
document.write( "in 1 trial is 0.48,\r\n" );
document.write( "\r\n" );
document.write( "\"4C3%2A%280.48%29%5E3%2A%281-0.48%29%5E%284-3%29\"\r\n" );
document.write( "\r\n" );
document.write( "\"4%2A%280.110592%29%2A%280.52%29%5E1\"\r\n" );
document.write( "\r\n" );
document.write( "\"4%2A%280.110592%29%2A%280.52%29\"\r\n" );
document.write( "\r\n" );
document.write( "\"0.23003136\"\r\n" );
document.write( "\r\n" );
document.write( "Round to 0.23, write as \"23%2F100\"\r\n" );
document.write( "\r\n" );
document.write( "Or do it on a TI-83 or 84 calculator.\r\n" );
document.write( "\r\n" );
document.write( "2ND, VARS, ALPHA, MATH\r\n" );
document.write( "\r\n" );
document.write( "If you get a screen with trials, p:, x value, Paste, \r\n" );
document.write( "make it read \r\n" );
document.write( "\r\n" );
document.write( "trials:4\r\n" );
document.write( "p:0.48\r\n" );
document.write( "x value:3\r\n" );
document.write( "Paste\r\n" );
document.write( "\r\n" );
document.write( "Highlight Paste\r\n" );
document.write( "\r\n" );
document.write( "Press ENTER\r\n" );
document.write( "\r\n" );
document.write( "Read:     binompdf(4,0.48,\r\n" );
document.write( "          3)\r\n" );
document.write( "\r\n" );
document.write( "Or if you get binompdf( make it read like that\r\n" );
document.write( "\r\n" );
document.write( "Press ENTER\r\n" );
document.write( "\r\n" );
document.write( "Read .23003136\r\n" );
document.write( "\r\n" );
document.write( "Edwin
\n" ); document.write( "
\n" );