Answer:
Each girl should sell at least 77 boxes.
Step-by-step explanation:
Considering the number of boxes and how many girls will them, just take [tex]\dfrac{100}{13} \approx 77[/tex]
The exact result is [tex]\dfrac{100}{13} = 76.923...[/tex], but [tex]76 \cdot 13 = 988[/tex] and [tex]77 \cdot 13 = 1001[/tex], therefore, 76 cannot be the result. So, each girl should sell at least 77 boxes.
