document.write( "Question 1027761: How many liters of a 40% salt solutions must be added to a 4 liters of a 10% salt solutions to obtain 30% salt solutions? \n" ); document.write( "

Algebra.Com's Answer #642956 by ikleyn(52794) $\"\"$ $\"About$

You can put this solution on YOUR website!
.
\n" ); document.write( "How many liters of a 40% salt solutions must be added to a 4 liters of a 10% salt solutions to obtain 30% salt solutions?
\n" ); document.write( "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "

\r\n" );
document.write( "Let x be the required amount (volume) of a 40% salt solution.\r\n" );
document.write( "\r\n" );
document.write( "Then the equation for the pure acid volume is \r\n" );
document.write( "\r\n" );
document.write( "0.4x + 0.1*4 = 0.3*(x + 4).\r\n" );
document.write( "\r\n" );
document.write( "Simplify and solve:\r\n" );
document.write( "\r\n" );
document.write( "0.4x + 0.4 = 0.3x + 1.2,\r\n" );
document.write( "\r\n" );
document.write( "0.4x - 0.3x = 1.2 - 0.4,\r\n" );
document.write( "\r\n" );
document.write( "0.1x = 0.8,\r\n" );
document.write( "\r\n" );
document.write( "x =  = 8.\r\n" );
document.write( "\r\n" );
document.write( "Answer. 8 liters of 40% salt solution is needed.\r\n" );
document.write( "

\n" ); document.write( " \n" ); document.write( "

\n" );