document.write( "Question 859700: Sam has a 10 gallon paint can with a mixture of 90% paint and 10% water. Sam needs an 80% 20% mixture. How much water does Sam needs to add? I know the answer is 1.25 gallons. I don't understand how this answer was calculated. I am trying to help my son, any help would be appreciated. \n" ); document.write( "

Algebra.Com's Answer #517909 by josgarithmetic(39617) $\"\"$ $\"About$

You can put this solution on YOUR website!
Main interest is about percent paint, starting with 10 gallons of 90% paint.\r
\n" ); document.write( "\n" ); document.write( "Let y = volume of water to use, to add to the 10 gallons of paint, to obtain 80% paint.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Only one needed equation.
\n" ); document.write( " $\"highlight%28%2810%2A90%29%2F%2810%2By%29=80%29\"$
\n" ); document.write( "Solve for y.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Percents were used, although the equation could have been done completely as decimal fractions. \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "It that equation as shown, enough for your son, or is more explanation or steps needed? \n" ); document.write( "

\n" );