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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

Three charges q_{1}=+3\mu C, q_{2}=+6\mu C and q_{3}=+8\mu C are located at (2,0)m (0,0)m and (0,3) coordinates respectively. Find the magnitude and direction acted upon q_{2} by the two other charges.Draw the correct graphical illustration of the problem above showing the direction of all forces.
Kate Reply
To solve this problem, we need to first find the net force acting on charge q_{2}. The magnitude of the force exerted by q_{1} on q_{2} is given by F=\frac{kq_{1}q_{2}}{r^{2}} where k is the Coulomb constant, q_{1} and q_{2} are the charges of the particles, and r is the distance between them.
Muhammed
What is the direction and net electric force on q_{1}= 5µC located at (0,4)r due to charges q_{2}=7mu located at (0,0)m and q_{3}=3\mu C located at (4,0)m?
Kate Reply
what is the change in momentum of a body?
Eunice Reply
what is a capacitor?
Raymond Reply
Capacitor is a separation of opposite charges using an insulator of very small dimension between them. Capacitor is used for allowing an AC (alternating current) to pass while a DC (direct current) is blocked.
Gautam
A motor travelling at 72km/m on sighting a stop sign applying the breaks such that under constant deaccelerate in the meters of 50 metres what is the magnitude of the accelerate
Maria Reply
please solve
Sharon
8m/s²
Aishat
What is Thermodynamics
Muordit
velocity can be 72 km/h in question. 72 km/h=20 m/s, v^2=2.a.x , 20^2=2.a.50, a=4 m/s^2.
Mehmet
A boat travels due east at a speed of 40meter per seconds across a river flowing due south at 30meter per seconds. what is the resultant speed of the boat
Saheed Reply
50 m/s due south east
Someone
which has a higher temperature, 1cup of boiling water or 1teapot of boiling water which can transfer more heat 1cup of boiling water or 1 teapot of boiling water explain your . answer
Ramon Reply
I believe temperature being an intensive property does not change for any amount of boiling water whereas heat being an extensive property changes with amount/size of the system.
Someone
Scratch that
Someone
temperature for any amount of water to boil at ntp is 100⁰C (it is a state function and and intensive property) and it depends both will give same amount of heat because the surface available for heat transfer is greater in case of the kettle as well as the heat stored in it but if you talk.....
Someone
about the amount of heat stored in the system then in that case since the mass of water in the kettle is greater so more energy is required to raise the temperature b/c more molecules of water are present in the kettle
Someone
definitely of physics
Haryormhidey Reply
how many start and codon
Esrael Reply
what is field
Felix Reply
physics, biology and chemistry this is my Field
ALIYU
field is a region of space under the influence of some physical properties
Collete
what is ogarnic chemistry
WISDOM Reply
determine the slope giving that 3y+ 2x-14=0
WISDOM
Another formula for Acceleration
Belty Reply
a=v/t. a=f/m a
IHUMA
innocent
Adah
pratica A on solution of hydro chloric acid,B is a solution containing 0.5000 mole ofsodium chlorid per dm³,put A in the burret and titrate 20.00 or 25.00cm³ portion of B using melting orange as the indicator. record the deside of your burret tabulate the burret reading and calculate the average volume of acid used?
Nassze Reply
how do lnternal energy measures
Esrael
Two bodies attract each other electrically. Do they both have to be charged? Answer the same question if the bodies repel one another.
JALLAH Reply
No. According to Isac Newtons law. this two bodies maybe you and the wall beside you. Attracting depends on the mass och each body and distance between them.
Dlovan
Are you really asking if two bodies have to be charged to be influenced by Coulombs Law?
Robert
like charges repel while unlike charges atttact
Raymond
What is specific heat capacity
Destiny Reply
Specific heat capacity is a measure of the amount of energy required to raise the temperature of a substance by one degree Celsius (or Kelvin). It is measured in Joules per kilogram per degree Celsius (J/kg°C).
AI-Robot
specific heat capacity is the amount of energy needed to raise the temperature of a substance by one degree Celsius or kelvin
ROKEEB
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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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