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Mathematics

Number concept, addition and subtraction

Addition

Educator section

Memorandum

1.1 7

1.2 4

1.3 2

1.4 7

1.5 4

2.1 432; 214; 1 346; 1 020; 8 421; 6 045

2.2 512; 294; 1 426; 1 100; 6 125

2.3 1 482; 1 264; 2 396; 2 070; 9 471; 7 095

3.

4.

4.1 26

4.2 66

4.3 34

4.4 44

4.5 94

4.6 49

4.7 49

4.8 351

4.9 368

4.10 9 984

4.11 32

4.12 48

4.13 48

4.14 6

4.15 24

4.16 96

4.17 132

4.18 7

4.19 15

4.20 44

5. 33 000; 43 000; 53 000; 63 000; 73 000; 83 000; 93 000; 103 000;

113 000; 123 000; 133 000

Leaner Section

Content

Activity: to be able to count correctly [lo 1.1]

To be able to calculate correctly [lo 1.8]

To be able to do mental arithmetic [lo 1.9]

1. In Mathematics it is important to count "visually". To be able to do this correctly, you must look carefully at the given figure. You must also read the questions carefully and with insight, because if you do not understand them, you will not count correctly! Let us start immediately with a challenge. Work with a friend and count:

1.1 How many dots are there in the circle? _______________________________

1.2 How many dots are there in the circle, and in the rectangle as well?

_____________________________________________________________________

1.3 How many dots are there in the circle, and in the rectangle and the triangle as well? ________________________________________________________________

1.4 How many dots are outside the circle? _______________________________

1.5 How many dots are in the rectangle, but not in the circle or the triangle? _____________________________________________________________________

2. In the previous activity you counted with small numbers. Let us now use greater numbers. It is important that you know the value of each digit (as we did in the previous Learning Unit) before you start adding. This will help you calculate the answers correctly. See whether you or your friend can say the correct answer first. If you are not sure, check the answer with a calculator.

2.1 Add 50 to each balloon’s number.

2.2 Add 130 to each balloon’s number.

2.3 Add 100 to each balloon’s number.

3. Now see whether you can do the following!

Use each of the numbers 4 ; 5 ; 6 ; 7 ; 8 ; 9 ; 10 ; 11 and 12 once only, so that the sum of the 3 numbers in any direction is always 21.

4. It saves a lot of time if one does not have to solve a problem with pencil and paper every time. That is why it is so important that you must be able to think quickly! Work on your own and complete the arithmetic test as quickly and accurately as possible. You have only three minutes!

a) 17 + 9 = _________________

b) 57 + 9 = _________________

c) 45 – 11 = _________________

d) 65 - 21 = _________________

e) Double 47: _________________

f) 17 + 19 + 13 = _________________

g) 23 + 19 + 7 = _________________

h) 210 + 120 + 21 = _________________

i) Double 184: _________________

j) 10 000 – 16 = _________________

k) Halve 64: _________________

l) Halve 96: _________________

m) 6 × 8 = _________________

n) 54 ÷ 9 = _________________

o) One quarter of 96 = _________________

p) 12 × 8 = _________________

q) _________________ ÷ 12 = 11

r) 63 ÷ _________________ = 9

s) (15 ÷ 15) × 15 = _________________

t) (56 + 63) + 44 = 56 + (_________________ + 63)

HOW DID YOU FARE?
MARK THE RELEVANT BOX:
I had all right!
I had more than half right!
I did not do well enough.

5. Now let us add even greater numbers. See if you can complete the following neatly and correctly. Start at 33 000 and add 10 000 at a time. Build yourself a "footpath" by colouring every block with the correct answer green.

33 000 40 000 58 000 85 000 93 000 102 000 110 000 133 000
38 000 43 000 60 000 83 000 96 000 103 000 111 000 123 000
41 000 53 000 62 000 73 000 99 000 107 000 113 000 121 000
32 000 55 000 63 000 71 000 100 000 109 000 116 000 119 000

DO YOU STILL REMEMBER?

If we want to programme the calculator to check the previous sum, we key in 33 000 + 10 000 = = =.

Use your calculator to check whether your “footpath” has been calculated correctly.

Assessment

Learning Outcome 1: The learner will be able to recognise, describe and represent numbers and their relationships, and to count, estimate, calculate and check with competence and confidence in solving problems.

Assessment Standard 1.1: We know this when the learner counts forwards and backwards in whole number intervals and fractions;

Assessment Standard 1.8: We know this when the learner estimates and calculates by selecting and using operations appropriate to solving problems;

Assessment Standard 1.9: We know this when the learner We know this when the learner performs mental calculations.

Questions & Answers

find the 15th term of the geometric sequince whose first is 18 and last term of 387
Jerwin Reply
I know this work
salma
The given of f(x=x-2. then what is the value of this f(3) 5f(x+1)
virgelyn Reply
hmm well what is the answer
Abhi
how do they get the third part x = (32)5/4
kinnecy Reply
can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
ninjadapaul
20/(×-6^2)
Salomon
okay, so you have 6 raised to the power of 2. what is that part of your answer
ninjadapaul
I don't understand what the A with approx sign and the boxed x mean
ninjadapaul
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
Salomon
I'm not sure why it wrote it the other way
Salomon
I got X =-6
Salomon
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
ninjadapaul
oops. ignore that.
ninjadapaul
so you not have an equal sign anywhere in the original equation?
ninjadapaul
hmm
Abhi
is it a question of log
Abhi
🤔.
Abhi
I rally confuse this number And equations too I need exactly help
salma
But this is not salma it's Faiza live in lousvile Ky I garbage this so I am going collage with JCTC that the of the collage thank you my friends
salma
Commplementary angles
Idrissa Reply
hello
Sherica
im all ears I need to learn
Sherica
right! what he said ⤴⤴⤴
Tamia
hii
Uday
hi
salma
what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
Kevin Reply
a perfect square v²+2v+_
Dearan Reply
kkk nice
Abdirahman Reply
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
Kim Reply
or infinite solutions?
Kim
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Al
y=10×
Embra Reply
if |A| not equal to 0 and order of A is n prove that adj (adj A = |A|
Nancy Reply
rolling four fair dice and getting an even number an all four dice
ramon Reply
Kristine 2*2*2=8
Bridget Reply
Differences Between Laspeyres and Paasche Indices
Emedobi Reply
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
Mary Reply
how do you translate this in Algebraic Expressions
linda Reply
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris 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
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
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
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
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
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
Hello
Uday
I'm interested in Nanotube
Uday
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
Prasenjit
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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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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