Final answer:
Juliet and Zach purchased a total of 120 pounds of grapes combined, as Juliet bought 4 12 lb. and Zach bought 6 12 lb., summing up to 120 pound.
Step-by-step explanation:
To find the total pounds of grapes purchased by Juliet and Zach, we need to add up the pounds of grapes they individually purchased. Juliet purchased 4 12 lb. of grapes, which is equal to 48 pounds (4 x 12). Zach purchased 6 12 lb. of grapes, which is equal to 72 pounds (6 x 12). Adding these two quantities together gives us a total of 120 pounds (48 + 72). Therefore, Juliet and Zach purchased a total of 120 pounds of grapes.