(1) From 20 10 to 20 1 1, the number of books borrowed in our school increased = 2336-2178 =158;

(2) The total number of students in the school is 20 1 1.

The average loan amount of junior middle school students is 1642÷80%=2052.5.

The amount of books borrowed per senior high school student is 252÷ 12%=2 100.

Then high school students borrow a lot of books per capita;

(3) Let the total number of students in the whole school be 1, 438+00 in 2065, and the per capita borrowing amount of junior middle school students be 1.520÷75% = 2026.7.

Then, at the beginning of 20 1 1, the amount of books borrowed by middle school students per capita was relatively large.