The table shows information about the heights, in cm, of a group of Year 9 girls. 150 cm
least height
median
greatest height
165 cm
170 cm
This stem and leaf diagram shows information about the heights, in cm, of a group
of 15 Year 9 boys.

15 8 99
16 4 5 7 7 8
17 0 3 4 4 7
18 02

Key: 15 | 8 represents 158 cm

Compare the distribution of the heights of the girls with the distribution of the heights of
the boys.

(Total for Question 7 is 3 marks)

look at the picture.

1.

ef : ab = 2 : 3

gf : cb = 2 : 3

gh : cd = 2 : 3

he : da = 2 : 3

2.

∠a ≅ ∠e

∠b ≅ ∠f

∠c ≅ ∠g

∠d ≅ ∠h

3.

use pythagorean theorem:

the length of the abcd trapezoid sides:

|ab| = 3 cm

|bc| = 10 cm

|cd| = 3(3) cm = 9 cm

|da| = 8 cm

the perimeter of abcd = 3 + 10 + 9 + 8 = 30 cm

the ratio of perimeters of the tarapezoids is equal 2 : 3.

substitute:

      cross multiply

      divide both sides by 3

(f+g)(x) = 3^x+10x+4x-2

      =3^x +14x-2

choice b