Number scale is constructed with a line and fixed length line segment. It is a line with numerical labels assigned to points, where the ratio of the distance between two points (PQ) and the given segment determines the label x of point P. This definition can be used to divide a line segment into equal parts to locate the point labeled by a rational number r/s. A number scale provides a graphical interpretation of rational number properties - points labeled by the same number coincide, larger numbers are farther right, and addition and multiplication of rational numbers have geometric meanings through similar triangles.

1. NUMBER SCALE
1. Devi Fitri Noviyanti
2. Yeni Nuraeni

2. Number scale is constructed by starting
with a line and a line segment of fixed
length.

3. DEFINITION
•Number scale is line on which the point
have been given numerical names or
labels.

4. •The rule of number scale that the labels of
point of P is x if the ratio of PQ to a given
segment is x with the understanding that P
is to the right of Q when x is positive and
to the left of Q if x is negative.

5. •This definition can be used along with the
parallel-line construction for dividing a line
segment into a number of equal parts to
locate the point on the number scale
whose label is the rational number r/s.

6. •The importance of the number scale lies
in the fact that we can use it to give a
graphical interpretation of the properties
of rational number.
Example:
•If r=s, the point R and S coincide and that.
•If r>s, R is to the right of S.
 moreover there is a simple interpretation
of addition.

7. •If R denotes the point was labeled is r the
point was label is –r is just as far from Q as
R is but on the other side of Q.

8. •Multiplication and division of rational
number also have geometric
interpretation but they require the use of
an auxiliary scale.

9. •We see from the similar triangle one
find that z/y=x/1 and z=xy, this
statement indicates multiplications.

10. •We see from the similar triangle one find
that z/1=x/y and z=x/y, this statement
indicates dividing.