Question 971365
{{{ ( 2 + x ) / ( 4 + x ) = .8 }}}
{{{ 2 + x = .8*( 4 + x ) }}}
{{{ 2 + x = 3.2 + .8x }}}
{{{ .2x =1.2 }}}
{{{ x = 6 }}}
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6 pints of yellow looks correct. You are
adding to the amount of yellow and also
the total volume of paint
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check:
{{{ ( 2 + x ) / ( 4 + x ) = .8 }}}
{{{ ( 2 + 6 ) / ( 4 + 6 ) = .8 }}}
{{{ 8/10 = .8 }}}
OK