Answer:
25%
Explanation:
box plots are all about quartiles:
in theory, 25% of the data should reside between the minimum and the first quartile
in theory, 25% of the data should reside between the first quartile and the median
in theory, 25% of the data should reside between the median and the third quartile
in theory, 25% of the data should reside between the third quartile and the maximum