The graph compares the ages of 100 randomly selected visitors at a beach in january and in july. two box and whisker plots showing beach visitors in january and july on a number line from 0 to 100. the upper plot represents the visitors in january. for this upper plot, the minimum number is 10, the maximum number is 78, the right side of the box is 60, the left side of the box is 30, and the bar in the box is at 40. the lower plot represents the visitors in july. for this lower plot, the minimum number is 1, the maximum number is 70, the right side of the box is 40, the left side of the box is 16, and the bar in the box is at 23. how many more visitors over the age of 40 were at the beach in january than in july?