2T Ratio and Proportion.notebook

1

November 25, 2013

Nov 7­12:13

Daily Practice 7.11.2013Q1. 12/3 ‐

1/5

Q2. Calculate the volume of a cuboid with length 8cm, breadth 4cm and height 2cm

Q3. Solve 4 + 3y = 13 + 2y

Q4. Find 4/5 of 251

Q5. Write out the 3 times tables up to 3 x 12

If finished ‐ fill in this magic square such that every row, column & diagonal add to the same amount

Nov 7­12:17

Today we are going to learn

how to simplify ratios.

Nov 7­12:17

Ratio 7.11.2013

Ratios are used to compare different amounts that are related to each other.

For example: The ratio of girls to boys in this class is

Nov 7­12:20

Ratio 7.11.2013

Chickens Goats Pigs

Farmer Brown has chickens, goats and pigs in his farmyard

He wants to separate them and put them in different pens.

The ratios

chickens : goats = __ : __

goats : chickens = __ : __

goats : pigs = __ : __

pigs : chickens = __ : __

Nov 7­12:25

Kate's box of magic tricks!

What is the ratio of:Rabbits: HatsHats: WandsWands: CloaksRabbits: cloaks

Nov 7­12:26

Simplifying ratios

If there are 6 dogs for every 3 people, how many dogs are there for every one person?

2T Ratio and Proportion.notebook

2

November 25, 2013

Nov 7­12:27

Simplifying ratios

If there are 6 dogs for every 3 people, how many dogs are there for every one person?

Nov 7­12:27

If there are 12 cakes for every 4 people, how many cakes are there for every one person?

Nov 7­12:27

If there are 10 houses for every 15 people, how many houses are there for every 3 people?

Nov 7­12:29

Ratio 7.11.2013

Simplifying Ratios:

Simplifying ratios works the same way as simplifying fractions. Divide by the highest common factor.

Examples: Simplify

(a) 14:21 (b) 35:42 (c) 36:72 (d) 15:20:35

Nov 7­12:28

Simplify these ratios

5 : 10 :

3 : 6 :

15 : 20 :

20 : 24 :

7 : 21 :

4 : 12 :

30 : 10 :

4 : 2 :

15 : 25 :

16 : 24 :

14 : 21 :

16 : 12 :

Nov 7­12:51

Daily Practice 8.11.2013

Q1. Simplify the ratio 25:150

Q2. 2.33 ‐ 1.9

Q3. State the nth term formula Position 1 2 3 4 5

for this table Term 6 11 16

Q4. Factorise 15ab ‐ 25b2

Q5. Write out the 4 times tables up to 4 x 12

2T Ratio and Proportion.notebook

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November 25, 2013

Nov 8­11:08

1/3  :  2

Unitary Ratio:

A unitary ratio is one in which one of the numbers is 1.

Make these such that they have a unitary ratio

Nov 7­12:32

Ratio calculations (Equivalent Ratios)

Examples:

1. In a recipe the ratio of butter to sugar is 2: 1 If the chef uses 50 grams of butter, how much sugar should they use?

2. If the ratio of girls to boys in S2 is 3:2 and there are 90 girls, how many boys are there?

Equivalent ratios (e.g. 3:2 is the same as 30:20) can be used to solve problems

Nov 11­12:53

Daily Practice 12.11.2013Q1. Round 7126 to the nearest 1000

Q2. ‐5 + (‐4)

Q3. Solve 5x ‐ 1 = 2x + 14

Q4. 32.15 ÷ 5

Q5. Calculate the height of the cuboid shown if the volume is 320cm3

x cm 

8 cm 2 cm 

Nov 11­12:55

Today we will be learning how to share a quantity in a given ratio.

Nov 7­12:38

Sharing in a ratio

Examples:

1. Share £30 in the ratio 3:2

2. Share 36 marbles in the ratio 3:4:5

Nov 7­12:39

Jerry and Sarah gathered 150 apples, they share the apples in the same ratio that they did the work. Jerry worked for one hour and Sarah worked for 5. How many apples does each get?

2T Ratio and Proportion.notebook

4

November 25, 2013

Nov 12­20:42

daily practice 13.11.2013Q1. Calculate the volume of a cube with sides of length 7cm

Q2. Simplify the ratio 24:36

Q3. Solve 7g + 2 = 20 + g

Q4. State the value of 3g2 when g = 4

Q5. Write out the 7 times table up to 7 x 12

Nov 12­21:15

Today we are going to learn about proportion

Homework Online Due 20.11.2013

Nov 13­07:50

ProportionProportion is used to compare part of a quantity to the whole quantity. Proportion can be expressed as a fraction, percentage or ratio.

For example: In a class of 8 boys and 12 girls, what proportion are girls?

8 or 212 3

Nov 12­21:16

Direct proportion means that when two quantities are in proportion, as one increases the other increases in the same ratio.

For example: The cost of a meal increases as the number of people increases.

Question example ‐ The cost of a bar of chocolate is 59p. Calculate the cost of 5 chocolate bars?

Proportion

People

Cost

Nov 12­21:16

Unitary proportion means finding the cost/size of one first.

Examples:

1. If 8 bowls cost £20. Calculate how much it would cost for 5

2. If 5 cinema tickets cost £42. How much would it cost for 7 tickets?

Proportion

Nov 13­10:16

Questions:

1. If 7 DVDs cost £56.70, calculate the cost of 3

2. If apples individually cost 53p each. Which is cheaper? Buying 7 apples individually or a bag of 7 for £3.50?

3. If the cost of a meal for 5 people is £125. How much would it cost for a meal for 8 people?

4. If a wheel turns 300 times in 4 minutes, how many times would it turn in 5 minutes?

5. If the cost of a school trip for 80 students is £1200. How much would it cost for 100 students?

6. Which is cheaper per can? 6 cans of juice for £2.94 or 18 for £9.20

7. A box factory produces 20 000 boxes in 8 hours, how much will it produce in 12 hours?

8. If £1 = €1.20, how much would £8 be in Euros?

9. If €1 = £0.80, how much would €60 be in pounds?

10. If it takes 5 men 3 hours to build a wall, how long will it take 10 men to build the same wall? (Inverse proportion)

20 divided by 8 = £2.50

£2.50 x

if 5 cinemA tickets cost cost of seven: 8.40 x 7 =

2T Ratio and Proportion.notebook

5

November 25, 2013

Nov 13­13:29

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Q1. Calculate the value of 2ab ‐ b2 if a = 3 and b = 2

Q2. Find the volume of a cube with side of length 9cm

Q3. Solve 4(x ‐ 1) = 24

Q4. Share £160 in the ratio 3:5

Q5. If a 4 pack of tinned tomatoes is £2.80 and single tins are 75p each, which is cheaper?

Nov 13­13:32

Today we are going to learn about inverse proportion.

Nov 12­21:31

Inverse propotion means as one quantity increases, the other decreaes in the same ratio.

For example: The number of hours worked decreases if the amount of workers increases.

Examples:

1. If it takes 5 people to lay a pipeline in 5 days, how long would it take one person to lay a pipeline?

Inverse Proportion

Nov 13­13:29

Daily Practice 15.11.2013Q1. Find 7% of 890

Q2. Solve 6y ‐ 3 = y ‐ 28

Q3. Multiply out 7(2y ‐ 1) + 4y

Q4. Simplify the ratio 1/4 : 3

Q5. Share £30 in the ratio 5:1

Nov 14­12:45

Today we are going to complete an assessment on ratio.