The box plot with the horizontal axis contains the markings “B R O” and “B R O P S O” from left to right. The vertical axis of the graph is labeled “Cost Function”, and ranges from 100 to 500 with an increment of 50 units. The data values in the bars are as follows: B R O: Lower Quartile: 325. Median: 370. Upper Quartile: 480. Minimum: 350. Maximum: 450. B R O P S O: Minimum: 140. Maximum: 150. Note: All numerical data values are approximated.
Chart box of solved 4 m castellated beam. Source: Authors' own work