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From this pdf, students will learn to develop an understanding of how to convert and write equivalent decimals and percentages and also:

1. To multiply and divide by 100.

2. To convert decimals to percentages.

3. To convert percentages to decimals.

1. To multiply and divide by 100.

2. To convert decimals to percentages.

3. To convert percentages to decimals.

1.
Converting between Fractions, Decimals and Percentages

Lesson 2: Decimals to Percentages

Lesson 2: Decimals to Percentages

2.
Learning Objective

To develop an understanding of how to convert and write equivalent

decimals and percentages.

Targeting Assessment Objective A01

Success Criteria

• To multiply and divide by 100.

• To convert decimals to percentages.

• To convert percentages to decimals.

To develop an understanding of how to convert and write equivalent

decimals and percentages.

Targeting Assessment Objective A01

Success Criteria

• To multiply and divide by 100.

• To convert decimals to percentages.

• To convert percentages to decimals.

3.
Quick Maths

Calculate each of the following without a calculator.

1. 45 × 1000 = 45 000 1. 95 ÷ 10 = 9.5 1. 82 ÷ 100 = 0.82

2. 990 × 10 = 9900 2. 485 × 100 = 48 500 2. 79.2 ÷ 1000 = 0.0792

3. 550 ÷ 10 = 55 3. 6.2 × 10 = 62 3. 0.48 × 10 = 4.8

4. 90 ÷ 10 = 9 4. 0.52 × 1000 = 520 4. 0.09 × 100 = 9

5. 8800 ÷ 100 = 88 5. 954 ÷ 100 = 9.54 5. 949.8 ÷ 10 = 94.98

6. 101 × 100 = 10 100 6. 102 ÷ 100 = 1.02 6. 346.5 ÷ 100 = 3.465

7. 646 × 10 = 6460 7. 9.82 × 10 = 98.2 7. 0.091 × 10 = 0.91

8. 1020 ÷ 10 = 102 8. 777 ÷ 1000 = 0.777 8. 4.2987 × 100 = 429.87

Calculate each of the following without a calculator.

1. 45 × 1000 = 45 000 1. 95 ÷ 10 = 9.5 1. 82 ÷ 100 = 0.82

2. 990 × 10 = 9900 2. 485 × 100 = 48 500 2. 79.2 ÷ 1000 = 0.0792

3. 550 ÷ 10 = 55 3. 6.2 × 10 = 62 3. 0.48 × 10 = 4.8

4. 90 ÷ 10 = 9 4. 0.52 × 1000 = 520 4. 0.09 × 100 = 9

5. 8800 ÷ 100 = 88 5. 954 ÷ 100 = 9.54 5. 949.8 ÷ 10 = 94.98

6. 101 × 100 = 10 100 6. 102 ÷ 100 = 1.02 6. 346.5 ÷ 100 = 3.465

7. 646 × 10 = 6460 7. 9.82 × 10 = 98.2 7. 0.091 × 10 = 0.91

8. 1020 ÷ 10 = 102 8. 777 ÷ 1000 = 0.777 8. 4.2987 × 100 = 429.87

4.
Did Someone Say ‘Pizza’ Again?

Two friends decide to buy a pizza and they see the following offers:

Buy one pizza Buy one pizza

0.3

and get and

35% !

extra get

free extra free!

Assuming the pizzas are the same size and base price,

how would you calculate the best offer?

Two friends decide to buy a pizza and they see the following offers:

Buy one pizza Buy one pizza

0.3

and get and

35% !

extra get

free extra free!

Assuming the pizzas are the same size and base price,

how would you calculate the best offer?

5.
Converting Decimals to Percentages

Convert 0.84 to a percentage = 84% When we convert a decimal to a

percentage, we multiply by 100

because percent means ‘per cent’

or ‘per 100’.

Thousands Hundreds Tens Units Tenths Hundredths Thousandths

0 8 4

We don’t need

this 0 here.

Convert 0.84 to a percentage = 84% When we convert a decimal to a

percentage, we multiply by 100

because percent means ‘per cent’

or ‘per 100’.

Thousands Hundreds Tens Units Tenths Hundredths Thousandths

0 8 4

We don’t need

this 0 here.

6.
Converting Decimals to Percentages

Convert 0.04 to a percentage = 4% When we convert a decimal to a

percentage, we multiply by 100

because percent means ‘per cent’

or ‘per 100’.

Thousands Hundreds Tens Units Tenths Hundredths Thousandths

0 0 4

We don’t need …or

this 0 here… here.

Convert 0.04 to a percentage = 4% When we convert a decimal to a

percentage, we multiply by 100

because percent means ‘per cent’

or ‘per 100’.

Thousands Hundreds Tens Units Tenths Hundredths Thousandths

0 0 4

We don’t need …or

this 0 here… here.

7.
Converting Decimals to Percentages

Convert each decimal to a percentage:

1. 0.55 55%

2. 0.42 42%

3. 0.05 5%

4. 0.68 68%

5. 1.24 124%

Convert each decimal to a percentage:

1. 0.55 55%

2. 0.42 42%

3. 0.05 5%

4. 0.68 68%

5. 1.24 124%

8.
Converting Decimals to Percentages

If we multiply a decimal by 100 when

converting it to a percentage, what do

you think we could do when converting

a percentage to a decimal?

We can divide by 100.

If we multiply a decimal by 100 when

converting it to a percentage, what do

you think we could do when converting

a percentage to a decimal?

We can divide by 100.

9.
Converting Percentages to Decimals

Convert 23% to a decimal = 0.23 When we convert a percentage to

a decimal, we divide by 100.

Thousands Hundreds Tens Units Tenths Hundredths Thousandths

2 0

3

We must make sure

we add a zero to the

units column as a

placeholder.

Convert 23% to a decimal = 0.23 When we convert a percentage to

a decimal, we divide by 100.

Thousands Hundreds Tens Units Tenths Hundredths Thousandths

2 0

3

We must make sure

we add a zero to the

units column as a

placeholder.

10.
Converting Percentages to Decimals

Convert 9% to a decimal = 0.09 When we convert a percentage to

a decimal, we divide by 100.

Thousands Hundreds Tens Units Tenths Hundredths Thousandths

0

9 0

We must add in …and here as

a zero here… a placeholder.

Convert 9% to a decimal = 0.09 When we convert a percentage to

a decimal, we divide by 100.

Thousands Hundreds Tens Units Tenths Hundredths Thousandths

0

9 0

We must add in …and here as

a zero here… a placeholder.

11.
Converting Percentages to Decimals

Convert each percentage to a decimal:

1. 88% 0.88

2. 46% 0.46

3. 1% 0.01

4. 30% 0.30 or 0.3

5. 100% 1.00 or 1

Convert each percentage to a decimal:

1. 88% 0.88

2. 46% 0.46

3. 1% 0.01

4. 30% 0.30 or 0.3

5. 100% 1.00 or 1

12.
F.D.P. Grid

Divide by 100

Multiply by 100

Divide by 100

Multiply by 100

13.
Your Turn

14.
Loop Cards

15.
Exit Ticket

Two friends decide to buy a pizza and they see the following offers:

Buy one pizza Buy one pizza

0.3

and get and

35% !

extra get

free extra free!

Assuming the pizzas are the same size and base price,

how would you calculate the best offer?

To convert 0.3 to a percentage, we multiply it by 100. This gives us 30%.

We know that this is less than 35%, so the first offer is the best.

Equally, we can divide by 100 to work out that 35% is 0.35.

Two friends decide to buy a pizza and they see the following offers:

Buy one pizza Buy one pizza

0.3

and get and

35% !

extra get

free extra free!

Assuming the pizzas are the same size and base price,

how would you calculate the best offer?

To convert 0.3 to a percentage, we multiply it by 100. This gives us 30%.

We know that this is less than 35%, so the first offer is the best.

Equally, we can divide by 100 to work out that 35% is 0.35.

16.