Final answer:
The ratio of cups to total dishes is 2:7.
Explanation:
The ratio of cups to total dishes is 2:7. To find this ratio, you add the number of cups and plates to determine the total dishes, which is 90. Then, you divide the number of cups (40) by the total dishes (90).
Learn more about ratios here:
https://brainly.com/question/40200110
