Starter activityStarter activity Simplify the following Simplify the following

fractions on a fractions on a whiteboard.whiteboard.

3/63/6

2/42/4

4/84/8

6/86/8

60/8060/80

7/217/21

21/70 21/70

90/10090/100

240/480240/480

Ratio and Ratio and ProportionProportion

L/O: L/O:

To know the difference between ratio To know the difference between ratio and proportion.and proportion.

To solve simple ratio and proportion To solve simple ratio and proportion problems. problems.

Ratio is a way of comparing two quantities, for example:

The ratio of red to blue is 1:3

This can also be said as:

“For every 1 red block there are 3 blue blocks.”

The ratio of red to blue is

2:6

For every red cube how many blue cubes are there?

For every 1 red cube there are three blue cubes.

Ratio of 1 to 3

1:3 This symbolic representation has the same meaning as the word statement but it read as ‘1 to 3’.

The smaller number is usually written first in a ratio.

Proportion is when you compare parts of a whole and is written as a fraction, for example:

The proportion of red blocks is ¼

This can also be said as: “In every 4 blocks 1 is red.”

What is the proportion of blue blocks?

What proportion of cubes are blue?¼

How many red cubes are there in every 4 cubes?

1 in every 4 cubes is red. This shows the proportion of red cubes to the whole number of cubes and can be written as a fraction

¼ of the cubes are red.

What proportion of the cubes are blue?

¾

So, we’ve compared the So, we’ve compared the number of blue and red cubes number of blue and red cubes

in two different waysin two different ways Remember: RATIO (For every) compares one amount with

another e.g 1:3.

PROPORTION (In every) is when you compare parts of a whole and is written as a fraction.

e.g 1/4

What is the ratio of blue to green?

2:3

What is the proportion of blue cubes?

4 = 2

10 5

What is the proportion of green cubes?

If Mark has 2 stamps and John If Mark has 2 stamps and John has 4, what ratio is this?has 4, what ratio is this?

2 : 4 2 : 4 1 : 21 : 2

If Mark has 200 stamps and John has 400 If Mark has 200 stamps and John has 400 stamps what ratio is this?stamps what ratio is this?

200 : 400 200 : 400 2 : 4 2 : 4 1:2 1:2

If William has 500 sweets and Becky has 1000 If William has 500 sweets and Becky has 1000 sweets, what ratio is this?sweets, what ratio is this?

500 : 1000 500 : 1000 5 : 10 5 : 10 1 :2 1 :2

There are ten biscuits on a plate. There are ten biscuits on a plate. Three of them are chocolate and seven Three of them are chocolate and seven

are plain.are plain. What is the ratio of chocolate to plain What is the ratio of chocolate to plain

biscuits?biscuits? There are 3 chocolates for every plain There are 3 chocolates for every plain

biscuit biscuit 3:73:7

What proportion of the biscuits are What proportion of the biscuits are chocolate?chocolate?

3 of the 10 are chocolate 3 of the 10 are chocolate 3 in 10 3/103 in 10 3/10

What proportion of the biscuits are plain?What proportion of the biscuits are plain? 7 of the 10 are plain 7 of the 10 are plain 7 in 10 7/107 in 10 7/10

Remember:

RATIO (For every) compares one amount with another

e.g 1:3.

PROPORTION (In every) is when you compare parts of a whole and is written as a fraction.

e.g ¼

How many boys are in our class? How many girls?

What is the ratio of boys to girls? What proportion of the class is boys? What proportion is girls?

During this activity you will have used the following skills:

Knowledge related to ratio and proportion.

Knowledge of fractions.

Knowledge of multiplication tables.

Ability to apply all of the above to a specific context or word problem.