Excel: Count as a Percentage of Another Count?

Math7-Smith-88
Math7-Smith-65
Math7-Smith-75
Math7-Smith-98
Math7-Smith-67
Tech7-Jones-77
Tech7-Jones-66
Tech7-Jones-45
Tech7-Jones-88
Tech7-Jones-75
Tech7-Jones-22
Tech7-Jones-77

Defined as: Course-Teacher-StudentScore

My report does not need to show who the students are, just the course and teacher and the following:

I need to report: What percentage of students in each Course received a score between (0-64, 65-74, 75-84, 85-100). So it looks like I need to Count1 = how many students in each course, then Count2 = how many students got scores within each range, and then use these 2 counts to report on what percentage count2 is of count1 in for each course. Any help with this would be most appreciated.