<< Chapter < Page Chapter >> Page >

Mathematics

Grade 5

Ordinary and decimal fractions

Module 49

Tables and checks to arrange and record data

Activity 1:

To use tables and checks to arrange and record data [lo 5.3]

1. Use your existing knowledge to complete the following table:

T U t h
E.g. 5 9 8 = 5 98 100 size 12{ { { size 8{"98"} } over { size 8{"100"} } } } {} = 5,98
1.1 3 6 = _____ = _____
1.2 1 7 = _____ = _____
1.3 3 6 = _____ = _____
1.4 4 2 8 5 = _____ = _____
1.5 4 7 0 3 = _____ = _____

Brain-teaser!

What will the following fractions look like if written as decimal fractions on the calculator?

1. 3 100 size 12{ { {3} over {"100"} } } {} ______

2. 9 100 size 12{ { {9} over {"100"} } } {} ______

3. 40 100 size 12{ { {"40"} over {"100"} } } {} ______

4. 80 100 size 12{ { {"80"} over {"100"} } } {} ______

5. 37 100 size 12{ { {"37"} over {"100"} } } {} ______

6. 59 100 size 12{ { {"59"} over {"100"} } } {} ______

How do the answers of 3 and 4 differ from the rest?

Why is this?

Did you know?

Normally we don’t write the noughts at the end of decimal fractions, but in the following cases we do:

a) When we work with money : R8,60 (shows how many cents there are).

b) When we time an athlete with a stop-watch : 7,30 seconds. This is how we give results to the hundredth of a second.

  1. When Mom buys material : 1,70 m (so that the saleslady knows exactly how many cm to cut).

Activity 2:

To recognise and represent numbers [lo 1.3.3]

1. It is sometimes difficult to determine exactly where a decimal number fits into the greater whole. A number line is a handy way of helping you to determine this, because it helps you to “see” the sequence of the numbers. Draw arrows and label with the letters given to indicate more or less where the following numbers will be on the number line:

A : 5,82

B : 5,99

C : 6,09

D : 6,24

Activity 3:

To use a series of techniques to do mental arithmetic [lo 1.10.2]

1. Let us play a game!

Work with a friend. Take turns. Close your eyes and press on any number in the diagram on the next page with the back of your pencil. Open your eyes and tell your friend what the number consists of:

e.g. 14,38 = 14 + 3 10 size 12{ { {3} over {"10"} } } {} + 8 100 size 12{ { {8} over {"100"} } } {}

Colour in every number you get right green. Your friend colours all his / her correct numbers blue. The one who has something wrong misses a turn. The one who has coloured in the most blocks, wins.

Activity 4:

To recognise and classify numbers in order to compare them [lo 1.3.3]

1. By now you know how to write tenths and hundredths as decimal fractions. Look very carefully at the following numbers. Replace the * with<,>or =.

Hint: You should break the numbers up as in the game above if you have any doubts about the correct answer.

1.1 1,7 * 1,07 _____

1.2 0,6 * 0,06 _____

1.3 0,58 * 0,9 _____

1.4 0,34 * 0,4 _____

1.5 2,05 * 2,5 _____

1.6 1,8 * 1,80 _____

Brain-teaser!

What does one quarter ( 1 4 size 12{ { { size 8{1} } over { size 8{4} } } } {} ) look like as a decimal fraction?

Can you write the following as decimal fractions?

a) 3 4 size 12{ { {3} over {4} } } {} : _____

b) 1 25 size 12{ { {1} over {"25"} } } {} : _____

c) 3 20 size 12{ { {3} over {"20"} } } {} : _____

d) 17 50 size 12{ { {"17"} over {"50"} } } {} : _____

Activity 5:

To use tables and checks in order to arrange and record data [lo 5.3]

1. Challenge!

Take a measuring tape and measure the height of five of your class mates (to 2 digits after the decimal comma). List your results in a table and number your friends from the shortest to the tallest.

Name Height Numbered:short to tall
1.1
1.2
1.3
1.4
1.5

Thousandths

Did you know?

When I write one thousandth 1 1000 size 12{ { {1} over {"1000"} } } {} as a decimal fraction, it will be 0,001.

Questions & Answers

what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
s. Reply
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
preparation of nanomaterial
Victor Reply
how to synthesize TiO2 nanoparticles by chemical methods
Zubear
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
Privacy Information Security Software Version 1.1a
Good
Berger describes sociologists as concerned with
Mueller Reply
Got questions? Join the online conversation and get instant answers!
QuizOver.com Reply

Get the best Algebra and trigonometry course in your pocket!





Source:  OpenStax, Mathematics grade 5. OpenStax CNX. Sep 23, 2009 Download for free at http://cnx.org/content/col10994/1.3
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Mathematics grade 5' conversation and receive update notifications?

Ask