Question 583841
Let {{{x}}} = liters of pure baking soda needed
{{{ .3*200 = 60 }}} liters of baking soda in 30% solution
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{{{ ( 60 + x ) / ( 200 + x ) = .6 }}}
{{{ 60 + x = .6*( 200 + x ) }}}
{{{ 60 + x = 120 + .6x }}}
{{{ .4x = 60 }}}
{{{ x = 150 }}}
150 liters of pure baking soda are needed
check:
{{{ ( 60 + 150 ) / ( 200 + 150 ) = .6 }}}
{{{ 210 / 350 = .6 }}}
{{{ 210 = .6*350 }}}
{{{ 210 = 210 }}}
OK