Fill in the blanks according to the statistics. Bookstore last week book sales statistics ① The day when books were sold the most was _ _ _ _ _ more than the day when books were sold the least. ② All of them were sold last week. (1)990-390=600 (volume)

A: The day when books are sold the most is 600 more than the day when books are sold the least.

(2) 480+390+522+400+550+990+805 = 4137 (volume)

A: * * * sold 4 137 books this week.

(3)(480+390+522+400+550+990+805)÷7

=4 137÷7

=59 1 (volume);

A: On average, 59 1 book is sold every day.

(4)(550-400)÷400

= 150÷400

=37.5%;

A: The number of books sold on Friday is 37.5% more than that on Thursday.

So the answer is: 600,465,438+037,5965,438+0,37.5.