Maths question

Find the area of the figure below. The steps have equal depths and heights.



Basically to find the area of such figure, we need to "break " the figure up into rectangles or squares so that we can find the area of rectangles or squares.

Formula for area of rectangle : length x breadth



Since the depth of the steps are equal ==> 90 divide by 3 = 30

Area of A= 105 x 30 = 3150

Since the height of the steps are equal ==> 105 divide by 3 = 35

Height of Rectangle B = 105-35 = 70

Area of B = 70 x 30 = 2100

Area of C = 35 x 30 = 1050

Area of figure = Area of A + Area of B + Area of C
= 3150 + 2100 + 1050
= 6300


Ans: 6300 cm2

Put on your thinking caps!

1. A wire is used to form a rectangle,12cm long and 4cm wide. The same length of wire is used to form a square.
a)Find the length of the wire used.
b)Find the area of the square formed by the wire.

Solution:

Perimeter of the rectangle = 12 + 4 + 12 + 4 = 32

a) Ans: 32 cm

32 divide 4 = 8

Each side of the square is 8cm.

Are of the square = 8 X 8 = 64

b) Ans: 64 centimetres square

2. A plane departed Singapore at 21 50 on Friday. It landed in Country P at 02 10.
(a) On which day did it reach Country P?
(b) How long was the flight?

Solution:

(a) Saturday

b) ans: 4 h 20 min

Try these!

1. ABCD and X are squares. Find the unshaded area of ABCD.

Solution:
Length BC = 6 + 4 = 10
Area of ABCD = 10 x 10 = 100
Area of X= 6 x 6= 36
Area of unshaded area = 100 - 36 = 64

Ans: 64cm2



2. Find the area of the figure below.





3. Mat played a computer game for 2h 50 min. Then he took a 30 minutes rest before playing for another 45 minutes. The clock on the wall showed 1620. At what time did he start playing his computer game?



4. Sally jogged for 3h 40 min. Bobby jogged for 2h 50 min. Bobby stopped jogging at the same time as Sally. If he stopped jogging at 14 50, (a) at what time did he start jogging? (b) at what time did Sally start jogging?

Area & Perimeter Games

My beloved children,

Do try out the following games on area & perimeter! Have fun!

1) http://www.bgfl.org/bgfl/custom/resources_ftp/client_ftp/ks2/maths/perimeter_and_area/index.html

2) http://www.mathplayground.com/area_perimeter.html


Do try out!

Love,
Mrs Yang

Area & Perimeter

Dearest beloved children,

I hope you do understand the difference between area and perimeter now.

Area is looking for the area inside the shape/figure.

Perimeter is looking for the total length of all the sides of the figure.

Do seek clarification from Miss Tan or me when I am back. Alternatively, you can read up your Maths TB.

Maths is all about practising. Do more practises and you will get the hang of it soon.

Thank you.

Cheers,

Mrs Yang