The number of students accepted to the university is 20,000 * 0.05 = <<20000*0.05=1000>>1,000 students

The number of students who choose to attend the university is 1,000 * 0.9 = <<1000*0.9=900>>900 students

# Answer

900
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
In the fall, 20,000 high school students apply to Harvard University for college. In the spring, 5% of those 20,000 students are accepted to the university. Of the students who are accepted, 90% choose to attend the university, and the other 10% choose to go to other schools. How many students choose to attend Harvard University?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
900
In the fall, 20,000 high school students apply to Harvard University for college. In the spring, 5% of those 20,000 students are accepted to the university. Of the students who are accepted, 90% choose to attend the university, and the other 10% choose to go to other schools. How many students choose to attend Harvard University?
train