Question 850342
Let {{{ x }}} = liters of the 80% solution needed
{{{ .8x }}} = liters of sulfuric acid in 80% solution
{{{ .3*3 = .9 }}} liters of sulfuric acid in 30% solution
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{{{ ( .9 + .8x ) / ( 3 + x ) = .6 }}}
{{{ .9 + .8x = .6*( 3 + x ) }}}
{{{ .9 + .8x = 1.8 + .6x }}}
{{{ .2x = .9 }}}
{{{ x = 4.5 }}}
4.5 liters of the 80% solution are needed
check:
{{{ ( .9 + .8x ) / ( 3 + x ) = .6 }}}
{{{ ( .9 + .8*4.5 ) / ( 3 + 4.5 ) = .6 }}}
{{{ ( .9 + 3.6 ) / 7.5 = .6 }}}
{{{ 4.5 = .6*7.5 }}}
{{{ 4.5 = 4.5 }}}
OK
The problem is poorly stated. I'm not sure this is
what they want, but you can figure out anything about
the problem using what's here. Hope this helps