1. The school lends 780 books to each class according to the ratio of the number of students in three classes of grade 6. There are 43 students in class 1, 42 students in class 2 and 45 students in class 3. How many books can each class borrow? 2. The perimeter of a rectangle is 5.6CM, and the ratio of length to width is 5:2. How many square centimeters is its area?

Class one 780 ÷ (43 + 42 + 45) × 43 = 258
Class 2 780 ÷ (43 + 42 + 45) × 42 = 252
Class 3 780-252-258 = 270
2. Width = 5.6 ／ 2 ／ (5 + 2) × 2 = 0.8
Length = 5.6 ／ 2 ／ (5 + 2) × 5 = 2
Area = 0.8 × 2 = 1.6 square centimeter

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