Unformatted text preview: Percentages
General Conversion between % Fractions and Decimals www.mathsrevision.com Percentages using a calculator Percentage rise (Increase) Percentage fall (Decrease) One quantity as a Percentage of another Percentage Profit / Loss Percentage Increase / Decrease
13 Feb 2012 Compiled by Mr. Lafferty Maths Dept. Starter Questions
General 1. www.mathsrevision.com Find t he area and perimet er of a square wit h lengt h 3 cm. 4. 56 + 2. 36  1. 2 Find an equivalent f ract ion 2. 3. 1 wit h denominat or 100 f or . 20
13 Feb 2012 Compiled by Mr. Lafferty Maths Dept. Percentages
General Learning Intention Success Criteria 1. To understand the term percentage. www.mathsrevision.com 1. To explain what the term percentage means and how it is connected to fractions and decimals. 2. Understand connection between percentages, fractions and decimals. 13 Feb 2012 Compiled by Mr. Lafferty Maths Dept. 31 out of a 100 Percentages
General It is common to express fractions using a denominator of a 100 www.mathsrevision.com 31 10 0 7 10 0 means 31 % means 7 % 13 Feb 2012 Compiled by Mr. Lafferty Maths Dept. 7 out of a 100 Percentages
General Q. Write down the following as a fraction and a decimal. www.mathsrevision.com 27 = 27 27% = 10 0 15 = 15 15% = 10 0 2 =2 2% = 10 0
13 Feb 2012 10 0 = 0 .2 7 10 0 = 0 .15 10 0 = 0 .0 2 Compiled by Mr. Lafferty Maths Dept. Percentages
General Convert these percentages to fraction and simply www.mathsrevision.com 1 20 = 20% = 10 0 5 75% 3 75 = = 10 0 4 60%
13 Feb 2012 3 60 = = 10 0 5
Compiled by Mr. Lafferty Maths Dept. Percentages
General www.mathsrevision.com Covert these fractions to percentages 1 1 10 10 0 = 10 % 10
3 20 3 2 0 10 0 = 15 % 4 5
13 Feb 2012 4 5 10 0 = 8 0 %
Compiled by Mr. Lafferty Maths Dept. Percentages
General www.mathsrevision.com Sandra got 15 out of 20 in an maths exam. What percentage is this. 15 20 15 2 0 10 0 = 7 5 %
Compiled by Mr. Lafferty Maths Dept. 13 Feb 2012 Franchesca has the Percentages best result.
General www.mathsrevision.com Franchesca got 45 out of 60 in her Maths exam and Michael got 21 out of 30 in an English exam. Who got the best result. 13 Feb 2012 45 60 21 30 45 6 0 10 0 = 7 5 %
Compiled by Mr. Lafferty Maths Dept. 2 1 3 0 10 0 = 7 0 % Percentages
General www.mathsrevision.com Now try Ex 1 Page 41 13 Feb 2012 Compiled by Mr. Lafferty Maths Dept. Starter Questions
General 1. Calculat e 1200 Simplif y 300 www.mathsrevision.com 2. 75 200 3. 4.
13 Feb 2012 1 Find of 65 10
Find highest number t hat divides bot h 14 and 35 wit hout leaving a remainder.
Compiled by Mr. Lafferty Maths Dept. Percentages
General Learning Intention Success Criteria 1. To know how to calculate a percentage using a calculator. 2. Show working. www.mathsrevision.com 1. To explain how to calculate a percentage of a quantity using a calculator. 13 Feb 2012 Compiled by Mr. Lafferty Maths Dept. of means multiple
General Percentages
Remember money 2 decimal places 450 Q. Find 17% of 450 17 10 0 = 17 450 10 0 www.mathsrevision.com = 7 6 .5 0 13 Feb 2012 Compiled by Mr. Lafferty Maths Dept. of means multiple
General Percentages Q. Find 4% of 70 4 10 0 =4 70 10 0 70 www.mathsrevision.com Remember !! money 2 decimal places = 2 .8 0 13 Feb 2012 Compiled by Mr. Lafferty Maths Dept. Percentages
General www.mathsrevision.com Now try Ex2a Ch4 (page 42) 13 Feb 2012 Compiled by Mr. Lafferty Maths Dept. Starter Questions
General 1.
www.mathsrevision.com Calculat e 45. 6 x 7 2. 3. 4.
13 Feb 2012 15 W rit e t he f ract ion as a percent age 100
Find 20% of 700 4 j ars of sweet s cost 2. 40. How much f or 3 j ars.
Compiled by Mr. Lafferty Maths Dept. Percentage Increase
General Learning Intention Success Criteria 1. Understand terms increase for percentages. 2. Calculate simple increases in percentages. www.mathsrevision.com 1. To explain some simple increases in percentages using shop prices. 13 Feb 2012 Compiled by Mr. Lafferty Maths Dept. Percentage Increase / Decrease
General Example 2 www.mathsrevision.com The total hours of sunshine in June was 260. The total for July was 5% higher than June.. What is the total hours of sunshine in July. 260 100
July Total Hours = 5 = 13 260 + 13 = 273
Created by Mr. Lafferty Maths Dept Simple Percentages
General www.mathsrevision.com Now try Exercise 2b Ch4 (page 44) 13 Feb 2012 Compiled by Mr. Lafferty Maths Dept. Starter Questions
General 1.
www.mathsrevision.com Calculat e 88. 37x 9 2. 3. 4.
13 Feb 2012 35 W rit e t he f ract ion as a percent age 100
Find 60% of 900 5 j ars of sweet s cost 6. 50. How much f or 4 j ars.
Compiled by Mr. Lafferty Maths Dept. Percentage Fall (Decrease)
General Learning Intention Success Criteria 1. Understand terms decrease for percentages. 2. Calculate simple decreases in percentages. www.mathsrevision.com 1. To explain some simple decreases in percentages using shop prices. 13 Feb 2012 Compiled by Mr. Lafferty Maths Dept. Percentage Fall (decrease)
General Example 1 www.mathsrevision.com In a sale the cost of a jumper is reduced by 10%. What is the sale price of the jumper. 35 100
Sale Price = 10 = 3.50
Original Price 35 35  3.50 = 31.50
Created by Mr. Lafferty Maths Dept Percentage Fall (decrease)
General www.mathsrevision.com Now try Exercise 2c Ch4 (page 47) 13 Feb 2012 Compiled by Mr. Lafferty Maths Dept. Starter Questions
General Q 1. W r it e t h e s e pe r e c e nt ag e s as d e c im a ls . www.mathsrevision.com (a) 4 0 % (b ) 15 % (c ) 4 5 % Q 2 . Find 6 0 % o f 7 2 0 . Q 3 . Find t h e ar e a o f t h e s h ape . 8cm 13 Feb 2012 Created by Mr. Lafferty Maths Dept. 6cm Calculating Percentages
General Learning Intention Success Criteria 1. To understand how to express "A" as a percentage of "B". 2. Solve problems in context. www.mathsrevision.com 1. To understand how to express "A" as a percentage of "B". 13 Feb 2012 Created by Mr. Lafferty Maths Dept. Calculating Percentages
General www.mathsrevision.com Linda scored 45 out of 100 in a Maths test. Write her score as a fraction in it simplest form ? Fraction = 9 45 = 10 0 2 0 What was her percentage score ?
13 Feb 2012 Created by Mr. Lafferty Maths Dept. 45 % Calculating Percentages
General www.mathsrevision.com My council tax has gone up by 60. It was 300 before the increase. Calculate the council tax increase as a percentage ? Increase = 60
% Increase
13 Feb 2012 60 60 = 100 300 300
Created by Mr. Lafferty Maths Dept. =20% Calculating Percentages
General www.mathsrevision.com My car has decreased in value to 3000. Before the decrease it was valued at 5000. Calculate the decrease as a percentage ? Increase = 5000 3000 = 2000
% decrease
13 Feb 2012 2000 2000 = 5000 5000
Created by Mr. Lafferty Maths Dept. 100 = 40% Calculating Percentages
General www.mathsrevision.com Extension booklet Ex 3E Now try Ch4 (page 13) 13 Feb 2012 Compiled by Mr. Lafferty Maths Dept. Starter Questions
General Q1. 0.5 + 5 x 8
www.mathsrevision.com Q2. Find g wh e n 3 7 g = 3 2 Q3.
I f b = 6, c = 3 Find c2 b 2
13 Feb 2012 Created by Mr. Lafferty Maths Dept. Profit and Loss
General Learning Intention Success Criteria 1. To know the meaning of the terms PROFIT and LOSS in terms of percentages.. 2. Apply knowledge to calculations. www.mathsrevision.com 1. To understand the terms profit and loss in terms of percentages. 13 Feb 2012 Created by Mr. Lafferty Maths Dept. Profit and Loss
General www.mathsrevision.com Profit : When you sell something for MORE than you bought it. PROFIT = Selling Price Buying Price Loss : When you sell something for LESS than you bought it. LOSS = Buying Price Selling Price
13 Feb 2012 Created by Mr. Lafferty Maths Dept. Profit and Loss
General www.mathsrevision.com If I buy a iPod for 200 and sell it for 220. What is my percentage profit. I have made a PROFIT of
% increase = 220 200 = 20 20 20 = 10 0 200 200
Created by Mr. Lafferty Maths Dept. = 10 % 13 Feb 2012 Profit and Loss
General www.mathsrevision.com I bought a bunch of flowers for 6.00 and tried to sell them for a profit. But I found it difficult to sell them. I sold them for 4.00 before they went off. I made a LOSS of
% decrease = 13 Feb 2012 6.00 4.00 = 2.00 1 2 .0 0 2 .0 0 = 10 0 = 3 3 % 6 .0 0 6 .0 0 3
Created by Mr. Lafferty Maths Dept. Profit and Loss
General www.mathsrevision.com Extension booklet Ex 4E Now try Ch4(page 16) 13 Feb 2012 Created by Mr. Lafferty Maths Dept. Starter Questions
General Q 1. W r it e t h e s e pe r e c e nt ag e s as d e c im a ls . www.mathsrevision.com (a) 7 5 % (b ) 12 .5 % (c ) 6 0 % Q 2 . Find 3 0 % o f 4 0 0 . Q 3 . Find t h e ar e a o f t h e s h ape . 10cm 13 Feb 2012 Created by Mr. Lafferty Maths Dept. 8cm Calculating Percentages
General Percentage Increase / Decrease
Learning Intention Success Criteria 1. To understand how to calculate percentage increase / decrease. 2. Solve problems in context. www.mathsrevision.com 1. To understand how to calculate percentage increase / decrease. 13 Feb 2012 Created by Mr. Lafferty Maths Dept. Calculating Percentages
General www.mathsrevision.com Example 1 : Frances scored 13 out of 20 in a Maths test. What was her percentage score? A % mark = B 13 13 = 10 0 20 20 =65% 13 Feb 2012 Created by Mr. Lafferty Maths Dept. Calculating Percentages
General Percentage Increase / Decrease Example 1 : Daniel was paid 20 per week. He got a rise to 22 per week. What was his percentage increase in pay ? A Actual Increase = 22 20 = 2 wage inc r e as e 2 = 10 0 % increase = o r ig inal pay 2 0 B
13 Feb 2012 Created by Mr. Lafferty Maths Dept. = 10 % Calculating Percentages
General Percentage Increase / Decrease Example 2 : A house in Barlanark bought for 40 000 in 2001 was sold last week for 50 000. Calculate the percentage increase in value? A Actual Increase = 50 000 40 000 = 10 000 inc r e as e 10 0 0 0 = 10 0 % increase = o r ig inal pr ic e 4 0 0 0 0
13 Feb 2012 B =25% Created by Mr. Lafferty Maths Dept. Calculating Percentages
General Percentage Increase / Decrease www.mathsrevision.com Extension Booklet Ex 5E Now try (page 17) 13 Feb 2012 Created by Mr. Lafferty Maths Dept. ...
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 Calculation, Decimal, Elementary arithmetic, Mr. Lafferty Maths Dept, Lafferty Maths Dept

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