Measurement notes

Volume worksheet 3-dimensional or 3D shapes are: a
solid figure or an object or shape
Step to calculate volume
that has 3 dimensions. They have
1) Work out normal area of BASE of shape
thickness and depth.
Eg: π r ; l x b;
2



2) Multiply area of base by the height

1000 cm3=¿ Litres= cm ÷1000
3



3) Remember units cubed


Only 3D shapes need apply 

Surface area
Definition: refers to the area of a 3D shape
Steps How to calculate Surface area:
Calculate the area of each side( surface) of
the shape/object, then add these totals
together.
1) Identify 3D shape
2) Look for a given formula. if one is
given see steps below if not read on…
3) Identify the shape of the sides of the
object. If need be break the shape up
into know shapes. Look at cube for
example you
Know it has 6 square faces. So
It is logical that if you work out what
the areaaof one square multiplied by 6
will give you the total space of all the
surface hat are visible.
4) Remember to have units squared and
remember to look for conversions of
units in the question

, Surface area example:

60cm Area of top and bottom= (length× breadth) × 2
60cm = (60 × 30) × 2
= 1800 cm 2 × 2
=3600 cm 2
40cm Area of Front and back = ( length×breadth) ×2
= (60 × 40) × 2
30cm
30cm =2400 × 2
= 4800cm 2


Area of sides = (length breadth) × 2
= (40 × 30) × 2
=1200 × 2
=2400 cm 2
Surface area of the box= 3600+4800+2400
= 10800 cm 2

Using a given forumula:
Steps:
1) Identify what the symbols mean.
2) Find the values accurately describing the number
3) Substitute the numbers for the letters.
Eg
60cm




40cm


30cm


B= Breadth
Forumula= 2(BH+BL+HL) H= Height
= 2( 30 × 40+ 30 × 60+ 40 × 60) L = Length
2
= 10800 cm