<image>A city conducted a sample analysis of the math test scores for the middle school to high school entrance exam of that year. The maximum possible score for the test was 100 points. After organizing the scores (all integers), a statistical chart was created as shown in the figure. Based on the information provided in the figure, answer the following questions:
(1) How many students' math scores were sampled for analysis?
(2) If a score of 80 and above (including 80) is considered excellent, what is the estimated rate of excellent students for that year?
(3) The total number of students who took the middle school to high school math exam that year was 22,000. Estimate the number of students who scored at least 60 points.

