<image>In a city, sample analysis was conducted on the 2015 junior high school to senior high school mathematics exam scores. The full score of the exam is 100 points, and the obtained scores (all positive integers) were organized to create a bar chart as shown in the figure. Based on the information provided in the chart, please answer the following questions:
(1) The total number of students whose mathematics scores were sampled for analysis in this city is ______;
(2) If a score of 80 or higher is considered excellent, the excellence rate of the 2015 junior high school to senior high school mathematics exam scores in this city is ______;
(3) In 2015, a total of 22,000 students took the junior high school to senior high school mathematics exams in this city. Please estimate the total number of students who passed (scored 60 points or above).