First Lessons in Arithmetic. Lesson XXVIII - counting by 2's, 3's, 4's, 5's, 6's

Here is the Lesson XXVIII in "First Lessons in Arithmetic". Print them out and use them as a math worksheet.



Counting is the mathematical action of repeatedly adding (or subtracting) one, usually to find out how many objects there are or to set aside a desired number of objects (starting with one for the first object and proceeding with an injective function from the remaining objects to the natural numbers starting from two), or for well-ordered objects, to find the ordinal number of a particular object, or to find the object with a particular ordinal number. Counting is also used (primarily by children) to demonstrate knowledge of the number names and the number system. Sometimes the term counting is used to mean the same as enumeration, i.e. finding the number of elements of a finite set.)

Counting sometimes involves numbers other than one; for example, when counting money, counting out change, when "counting by twos" (2, 4, 6, 8, 10, 12…) or when "counting by fives" (5, 10, 15, 20, 25…).