4. While working on fruit harvesting, class 5A collected 560 kg of apples, 5B - 595 kg, and 5V - 735 kg. All the collected apples were packed into boxes, with each box containing the same maximum possible number of kilograms. How many such boxes were required for each class?
4. The number of kilograms of apples in each box is the greatest common divisor of the numbers 560, 595, and 735. Since $560=2^{4} \cdot 5 \cdot 7, 595=5 \cdot 7 \cdot 17$ and $735=3 \cdot 5 \cdot 7^{2}$, then GCD $(560,595,735)=35$. This means that 35 kg of apples were placed in each box. Then the first squad needed 16 boxes $(560: 35=16)$, the second squad needed 17 boxes $(595: 35=17)$, and the third squad needed 21 boxes $(735: 35=21)$.