document.write( "Question 1177705: A box contains 3 blue and 4 red marbles while another box contains 2 blue and 5 red marbles. A marble drawn at random from one of the boxes turns out to be blue. What is the probability that it came from the first box? \n" ); document.write( "
Algebra.Com's Answer #806829 by ikleyn(53765)\"\" \"About 
You can put this solution on YOUR website!
.
\n" ); document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "The probability is\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "     P = \"%28%283%2F7%29%29%2F%28%283%2F7%29+%2B+%282%2F7%29%29\" = \"3%2F5\" = 0.6 = 60%.     ANSWER\r\n" );
document.write( "
\r
\n" ); document.write( "\n" ); document.write( "Solved.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "The formula used is self-explanatory.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" );