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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

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Akash Reply
it is a goid question and i want to know the answer as well
Maciej
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.
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.
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Do you know which machine is used to that process?
s.
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for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
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or in general
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in general
s.
Graphene has a hexagonal structure
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what's the easiest and fastest way to the synthesize AgNP?
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Cied
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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
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AMJAD
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Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
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AMJAD
what is system testing
AMJAD
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
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anybody can imagine what will be happen after 100 years from now in nano tech world
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after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
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Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
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I'm interested in Nanotube
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Source:  OpenStax, Mathematics grade 5. OpenStax CNX. Sep 23, 2009 Download for free at http://cnx.org/content/col10994/1.3
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