AREA AND VOLUMEForm 1 Mathematics

Chapter 7

REMINDER Lesson requirement

Textbook 1B Workbook 1B Notebook Folder

Before lessons start Desks in good order! No rubbish around! No toilets!

RESULT OF CBQ (CH. 9) Result of Close Book Quiz

Full mark: 40 and 10 bonus Highest: 44 Lowest: 10 Average: 23.8 Number of students between 10 – 19: 13 Number of students between 0 – 9:

0 Major Problems

Cannot get the drawing in rotation Cannot get the coordinates in transformation Mix up the rotation and reflection

RESULT OF CBQ (CH. 9) Result of Close Book Quiz 9th place: KO Ka Chung Boston

LIN Long Chak, Vincent 8th place: FU Ling Yin, Larry 7th place: LAU Cheuk Hei, Anson 6th place: CHEN Yi, David 5th place: CHAN Tsz Long, Sam 4th place: YUEN Tin Wai, Timmy 2nd place: LI Ming Chun, Edward

WU SHAN Hao Yi 1st place LI Sai Kong

Congratulations!!!!!! Well done!!!!!!

AREA OF PLANE FIGURES (P.2)

1. Area of triangle

2. Area of square

3. Area of rectangle

= length length

= length width

= base height12

AREA OF PLANE FIGURES (P.2)

4. Area of parallelogram

5. Area of trapezium

= base height

= sum of lengths of parallel sides height12

CALCULATING AREAS (P.3) Splitting Method

Filling Method

Area of the figure

= 18 cm2

12

= 3 3 + (3 + 6) 2 cm2

Area of the figure

= 38 cm2

= 10 4 – 2 2 cm212

TIME FOR PRACTICE Pages 10 – 11 of Textbook 1B

Questions 5 – 18 Pages 1 – 3 of Workbook 1B

Questions 1 – 5

WORKBOOK

WORKBOOK

16 36 10

260 cm2

36 36 10

(18 26) cm2

= 468 cm2

260 468

728 cm2

WORKBOOK

3 3

18 cm2

728 18

710 cm2

VOLUME OF SIMPLE SOLIDS (P.3)

1. Volume of cube

2. Volume of cuboid

= length length length

= length width height

PRISMS (柱體 , P.12) A solid with uniform cross-

section in the shape of a polygon is called a prism.

A prism is named and classified according to the shape of its base.

The perpendicular distance between the two parallel bases of a prism is called its height (or length).

The faces (other than the two bases) of a prism are called lateral faces.

base

base

Triangular prism

height

lateral faces

VOLUME OF PRISMS (P.17) Volume = area of base height

e.g. Volume of the solid = 260 20 cm3

= 5200 cm3

SURFACE AREAS OF PRISMS (P.14) Total surface area

= areas of the two bases + total area of all lateral faces

e.g. Total surface area of the solid = [2 260 + 6 (20 10)] cm2

= 1720 cm2

VOLUME OF PRISMS Volume of the triangular prism = ?

Area of the base of the prism= ( 7 4 2 ) cm2

= 14 cm2

So, the volume= ( 14 10 ) cm3

= 140 cm3

VOLUME OF PRISMS Volume of the rectangular prism (cuboid) = ?

The volume= [ ( 5 3 ) 6 ] cm3

= 90 cm3

The volume= [ ( 3 6 ) 5 ] cm3

= 90 cm3

The volume= [ ( 5 6 ) 3 ] cm3

= 90 cm3

VOLUME OF PRISMS Find the volume

of the prism.

Area of base

Volume of prism

= (12 7 – 8 5) cm2

= 44 cm2

= 44 11 cm3

= 484 cm3

VOLUME & SURFACE AREA OF PRISMS The figure shows a gold ingot in

the shape of a prism. Its base is a trapezium, and the other faces are rectangles. If the volume of the gold ingot is 540 cm3, find(a) the value of d,(b) the total surface area of the gold ingot.

(a) Area of trapezium

∴ The volume of the gold ingoti.e. 36d = 540 d = 15

(b) Total surface area of the gold ingot= [2 36 + 2 (15 5) + 15 12 + 15 6] cm2

= 492 cm2

12= (6 + 12) 4 cm2

= 36 cm2

= 36d cm3

TIME FOR PRACTICE Pages 22 – 23 of Textbook 1B

Questions 10 – 20 Pages 6 – 7 of Workbook 1B

Questions 3 – 6

WORKBOOK

WORKBOOK

8 8 8

512

5 10 4

200 cm3

4 3 d

12d cm3

512200 12d

12d = 312

26

WORKBOOK 2.5 1 6

15 cm2

19 15

4 cm2

4

2 cm2

2 2.5

5 cm3

1 2 3

6 cm3

6 cm3 5 cm3

B

REMINDER Missing Homework, Re-do Homework

Today! SHW (I)

Today! SHW (II)

22 Mar (Fri) Open Book Quiz

22 Mar (Fri) Close Book Quiz

26 Mar (Tue)

Enjoy the world of Mathematics!

Ronald H

UI