Each word, one, two, three, four, five, six, &c., points out how many things are spoken of. These words are called NUMBERS. Hence, NUMBERS are expressions for one or more things of the same kind. 2. The unit of a number is one of the equal things which the number expresses. Thus, if the number express six apples, one apple is the unit; if it express five pounds of tea, one pound of tea is the unit; if ten feet of length, one foot is the unit; if four hours of time, one hour is the unit. 1. What is a single thing called? One and one? Two and one? Three and one? Four and one? Five and one? Six and Seven and one? &c. What are Numbers? one? 2. What is the unit of a number? What is the unit of the number six apples? Of the number five pounds of tea? Of the number ten feet? Of the number four hours? 3. ARITHMETIC treats of numbers. Numbers are expressed by certain characters, called figures. There are ten of these characters, and they are the alphabet of the arithmetical language. They are O which is called a cipher, or Naught, We see from the language of figures, that 1 expresses a single thing, or a unit of a number. two things of the same kind, or two units. three things 3 128488 9 four things five things six things seven things eight things nine things or three units. or four units. or five units. or six units. or seven units. or eight units. or nine units. 4. The character 0 is used to denote the absence of. a thing. Thus, to express that there are no apples in a basket, we write, the number of apples is 0. The nine other figures are called, significant figures, or Digits. 5. We have no separate character for the number ten. If we wish to express it by figures, we must combine the characters already known. This we do by writing 0 on the right hand of the 1; thus, 10, which is read ten. 3. Of what does arithmetic treat? How are How many figures are there? Name them. called? How many things does 1 express? does 2 express? How many units in 3? In 4? In 8? In 9? numbers expressed? What may they be How many things In 5? In 6? In 7? 4. What does 0 express? What are the other nine figures called? 5. Have we a separate character for ten? How do we express ten? To how many units 1 is ten equal? May we consider it a single unit? Of what order? |