Similarity

It is the comparison between two or more quantities.

(a)  

It is the equality of two ratios.

(a)  

These are polygons with congruent corresponding angles and proportional corresponding sides.

(a)  

It is the uniform ratio of the corresponding proportional sides of polygons.

(a)  

If there are two pairs of proportional side and congruent  

  angles between them then the two triangles are similar by (a)   .

There are 10 notebooks and 11 ballpens in a box. What is the ratio of ballpens to notebooks?

• 10 : 11

• 11 : 10

• 21 : 10

• 21 : 11

Which of the following is NOT an example of a proportion?

• 1 : 2 = 2 : 4

• 1 : 3 = 5 : 15

• 1 : 4 = 12 : 16

• 1 : 1 = 8 : 8

• 2

• 2.5

• 10

• 30

Which side corresponds to BC?

• DE

• DF

• EF

• GH