Answer: 15
Explanation:
Since we are informed that in exchange for 5 eclaire boxes, that Luna gets, she decided to give 1 eclaire box for free.
Then, the number of eclaires boxes that they can buy from Luna using 77 claire boxes will be:
= 77 / 5
= 15 2/5
= 15 approximately
They'll get 15 boxes of eclaires from Luna.