The greatest common divisor of 1 60,40 is 20, that is, this rectangular piece of paper can be cut into squares with a maximum side length of 20 cm, and the number is 6.

(60×40)÷ (20×20)=6

The greatest common divisor of 2, 56 and 12 is 4, that is, the longest length of each paragraph is 4dm, and 1 * * can be cut (56+ 12)÷4= 17.