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Mathematics

Percentages

Educator section

Memorandum

17.4

a) R179,97

b) R254,58 (rounded off)

c) R10 665

d) R16 794,75

17.5.2

a) 10,7%

b) 10%

Leaner section

Content

Activity: percentages – discount and increases [lo 1.7, lo 2.7.1]

17. PERCENTAGES – DISCOUNT AND INCREASES

17.1 Look at the following advertisements

17.2 Did you know?

COST PRICE : The amount that the dealer / trader / merchant pays for an article

MARKED PRICE : This is the price of the article

SELLING PRICE : This is the price after discount

PROFIT : Sale price – cost price

17.3 Work together with a friend through the following problem and solutions:

(i) The price of a tub of margarine is R6,99. If the price is going to rise by 10 %, how much will you have to pay for the margarine in the future?

a) New price is R6,99 + 10% of R6,99= R6,99 + 70 c (rounded off)= R7,69

b) New price is (100 + 10)% of R6,99

= 110% of R6,99

= 110 100 × 699 1 size 12{ {}=` { { size 8{"110"} } over { size 8{"100"} } } times { { size 8{"699"} } over { size 8{1} } } } {}

= R7,69 (rounded off)

Which method do you choose? ..................................................

Why? ……………………………………………………………………………

(ii) Top Teenage T-shirts have a 20 % discount on all T-shirts. If the T-shirt originally cost R189,90, what will you pay for it now?

a)

I only pay 80% (100% - 20% discount)

Thus: 80 100 × 189 , 90 1 size 12{ { { size 8{"80"} } over { size 8{"100"} } } times { { size 8{"189","90"} } over { size 8{1} } } } {}

= R 151, 92

b)

20% of R189,90 = 20 100 × 189 , 90 1 size 12{ { { size 8{"20"} } over { size 8{"100"} } } times { { size 8{"189","90"} } over { size 8{1} } } } {}

The discount is thus R37,98

I pay R189,90 – R37,98 = R151,92

Which method do you choose? ..................................................

Why?

17.4 What will you pay for the following items?

17.5.1 Important to remember!

17.5.2 Divide into groups of three. Can you calculate how much % discount was given on the following items?

17.5.3 Explain your method(s) to the rest of the class.

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

Learning Outcome 2: The learner will be able to recognise, describe and represent patterns and relationships, as well as to solve problems using algebraic language and skills.

Assessment Standard 2.7: We know this when the learner determines, analyses and interprets the equivalence of different descriptions of the same relationship or rule presented:

2.7.1 verbally.

Questions & Answers

explain and give four Example hyperbolic function
Lukman Reply
The denominator of a certain fraction is 9 more than the numerator. If 6 is added to both terms of the fraction, the value of the fraction becomes 2/3. Find the original fraction. 2. The sum of the least and greatest of 3 consecutive integers is 60. What are the valu
SABAL Reply
1. x + 6 2 -------------- = _ x + 9 + 6 3 x + 6 3 ----------- x -- (cross multiply) x + 15 2 3(x + 6) = 2(x + 15) 3x + 18 = 2x + 30 (-2x from both) x + 18 = 30 (-18 from both) x = 12 Test: 12 + 6 18 2 -------------- = --- = --- 12 + 9 + 6 27 3
Pawel
2. (x) + (x + 2) = 60 2x + 2 = 60 2x = 58 x = 29 29, 30, & 31
Pawel
ok
Ifeanyi
on number 2 question How did you got 2x +2
Ifeanyi
combine like terms. x + x + 2 is same as 2x + 2
Pawel
Mark and Don are planning to sell each of their marble collections at a garage sale. If Don has 1 more than 3 times the number of marbles Mark has, how many does each boy have to sell if the total number of marbles is 113?
mariel Reply
Mark = x,. Don = 3x + 1 x + 3x + 1 = 113 4x = 112, x = 28 Mark = 28, Don = 85, 28 + 85 = 113
Pawel
how do I set up the problem?
Harshika Reply
what is a solution set?
Harshika
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Rofiqul
hello, I am happy to help!
Shirley Reply
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Abdullahi
hi mam
Mark
I need quadratic equation link to Alpa Beta
Abdullahi Reply
find the value of 2x=32
Felix Reply
divide by 2 on each side of the equal sign to solve for x
corri
X=16
Michael
Want to review on complex number 1.What are complex number 2.How to solve complex number problems.
Beyan
yes i wantt to review
Mark
use the y -intercept and slope to sketch the graph of the equation y=6x
Only Reply
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Seidu Reply
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Darius
hello, if you have a question about Algebra 2. I may be able to help. I am an Algebra 2 Teacher
Shirley Reply
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Seidu
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Opoku
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Tric Reply
4
Trista
x-2y+3z=-3 2x-y+z=7 -x+3y-z=6
Sidiki Reply
can you teacch how to solve that🙏
Mark
Solve for the first variable in one of the equations, then substitute the result into the other equation. Point For: (6111,4111,−411)(6111,4111,-411) Equation Form: x=6111,y=4111,z=−411x=6111,y=4111,z=-411
Brenna
(61/11,41/11,−4/11)
Brenna
x=61/11 y=41/11 z=−4/11 x=61/11 y=41/11 z=-4/11
Brenna
Need help solving this problem (2/7)^-2
Simone Reply
x+2y-z=7
Sidiki
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Mehri Reply
-1
Shedrak
the operation * is x * y =x + y/ 1+(x × y) show if the operation is commutative if x × y is not equal to -1
Alfred Reply
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Kimberly Reply
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August Reply
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How do i figure this problem out.
how do you translate this in Algebraic Expressions
linda Reply
why surface tension is zero at critical temperature
Shanjida
I think if critical temperature denote high temperature then a liquid stats boils that time the water stats to evaporate so some moles of h2o to up and due to high temp the bonding break they have low density so it can be a reason
s.
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
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Source:  OpenStax, Mathematics grade 7. OpenStax CNX. Sep 16, 2009 Download for free at http://cnx.org/content/col11075/1.1
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