Question 304985
Let {{{x}}} = quarts of grape juice needed
{{{1.2x}}} = cost of grape juice needed
{{{.9*3 = 2.7}}} = cost of apple juice used
In words:
(cost of all juice)/(total quarts of all juice) = $1/(1 quart)
{{{(1.2x + 2.7)/(x + 3) = 1}}}
{{{1.2x + 2.7 = x + 3}}}
{{{.2x = .3}}}
{{{x = 1.5}}} quarts of grape juice needed