1. The problem asks for the value below which 75% of the widths fall, based on the box plot. 2. In a box plot, the 75th percentile corresponds to the upper edge of the box, also called the third quartile (Q3). 3. From the description, the box extends roughly from 20 cm to 30 cm, so the upper edge of the box is about 30 cm. 4. Therefore, 75% of the widths were less than approximately $30$ cm. Final answer: 75% of the widths were less than $30$ cm.