Multiplication and division is the learning content of Unit 3 P48~P49 in the first volume of the fourth grade of primary school mathematics published by Beijing Normal University.

Multiplication and distribution law refers to the sum of two numbers multiplied by one number. You can multiply them by this number first and then add them up.

(a+b)×c=a×c+b×c (letter) a×c+b×c=(a+b)×c (letter variant).

□× (△+☆) = △×××+☆××× (illustrated) △××××+☆×× = □× (△+☆)) (illustrated variant).

Reverse application of multiplication and distribution law;

35×37+65×37

=37×(35+65)

=37× 100

=3700

58×55-58×35

=58×(55-35)

=58×20

= 1 160