Question 536493
Let {{{x}}} = quarts of pure pineapple juice needed
given:
{{{ .15*8 = 1.2 }}} quarts of pure pineapple juice in 15% drink
--------------
In words:
( quarts of pure pineapple juice ) / ( total quarts of drink ) = 50%
{{{ ( 1.2 + x ) / ( 8 + x ) = .5 }}}
{{{ 1.2 + x = .5*( 8 + x ) }}}
{{{ 1.2 + x = 4 + .5x }}}
{{{ .5x = 4 - 1.2 }}}
{{{ .5x = 2.8 }}}
{{{ x = 2.8/.5 }}}
{{{ x = 5.6 }}}
5.6 quarts of pure pineapple juice are needed
check:
{{{ ( 1.2 + 5.6 ) / ( 8 + 5.6 ) = .5 }}}
{{{ 6.8 / 13.6 = .5 }}}
{{{ 6.8 = .5*13.6 }}}
{{{ 6.8 = 6.8 }}}
OK