Question 956457
[ lemon concentrate ] / [ water ] = {{{ 2/5 }}}
[ lemon concentrate ] / [ lemon concentrate + water ] = {{{ 2/( 2 + 5 ) }}}
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Let {{{ x }}} = liters of lemon concentrate used
{{{ 2/7 = x/14 }}}
{{{ 4/14 = x/14 }}}
{{{ x = 4 }}}
4 litres of lemon concentrate are needed