Answer:
The number of quarts of carrot juice used is approximately 0.3333.
Explanation:
The proportional relationship between the quarts of prune juice (p) and carrot juice (c) in the recipe is given as;
4p = 12c
Thus for 1 quart of prune juice, the quarts of carrot juice required can be determined by;
i.e p = 1
So that,
4 x 1 = 12c
4 = 12c
c =

=

= 0.3333
The number of quarts of carrot juice used is approximately 0.3333.