Fractions decimals percentages - Nuffield Foundation

[Pages:14]Fractions, decimals and percentages

This activity is about converting between fractions, decimals and percentages.

Information sheet

Converting between decimals and fractions

To change a decimal to a fraction: use the place value of the last digit

? 5

For example

0.85 =

85 100

=

17 20

? 5 hundredths

On a calculator press: 85 a b c 100 =

To change a fraction to a decimal: divide the top by the bottom

For example

4 5

= 4 5 = 0.8

Converting between percentages and fractions or decimals

To write a % as a fraction or decimal: divide by 100

For example 64% = 64 100 = 0.64

or

64% =

64 100

=

16 25

On a calculator press: 64 a b c 100 =

To write a decimal or fraction as a %: multiply by 100 For example 0.125 = 0.125 100 = 12.5%

2 5

=

2 5

100

(i.e.

2 5

of 100%) = 40%

or

2 5

= 2 5 100 = 40%

On a calculator press: 2 a b c 5 100 = 40%

Nuffield Free-Standing Mathematics Activity `Fractions, decimals and percentages' Student sheets ? Nuffield Foundation 2012 downloaded from

Copiable page 1 of 14

Try these

1 Write these decimals as fractions:

0.3 = .............

0.5 = ............. 0.6 = ............. 0.02 = .............

0.05 = .............

0.25 = ............. 0.36 = ............. 0.125 = .............

2 Write these fractions as decimals:

7 10

= ...................

1 5

=

...................

2 5

= ...................

3 4

= .....................

7 8

= ...................

2 3

=

...................

9 20

=...................

7 25

=

.....................

3 Write these percentages as decimals:

3% = .............

30% = .............

25% = .............

80% = .............

8% = .............

12% = .............

67% = .............

17.5% = .............

Nuffield Free-Standing Mathematics Activity `Fractions, decimals and percentages' Student sheets ? Nuffield Foundation 2012 downloaded from

Copiable page 2 of 14

4 Write these percentages as fractions:

20% = .............

75% = .............

5% = .............

30% = .............

40% = .............

15% = .............

24% = .............

35% = .............

5 Write these decimals as percentages:

0.25 = .............

0.5 = .............

0.7 = .............

0.07 = .............

0.45 = .............

0.09 = .............

0.4 = .............

0.375 = .............

6 Write these fractions as percentages:

1 10

= .............

1 5

=

.............

9 10

=

.............

3 4

= .............

4 5

= .............

17 20

= .............

1 3

=

.............

2 3

= .............

Nuffield Free-Standing Mathematics Activity `Fractions, decimals and percentages' Student sheets ? Nuffield Foundation 2012 downloaded from

Copiable page 3 of 14

At the end of the activity

Explain how to convert ...

? a decimal to a fraction ? a fraction to a decimal ? a percentage to a fraction or decimal ? a fraction or decimal to a percentage.

Give some examples of real contexts where ...

? decimals are used ? fractions are used ? percentages are used.

Nuffield Free-Standing Mathematics Activity `Fractions, decimals and percentages' Student sheets ? Nuffield Foundation 2012 downloaded from

Copiable page 4 of 14

Fractions, decimals and percentages Fractions to decimals to percentages

Complete this table.

Fraction

1 10 1 5 3 10 2 5 1 2 3 5 7 10 4 5 9 10 1 4 3 4

Decimal

Percentage

Nuffield Free-Standing Mathematics Activity `Fractions, decimals and percentages' Student sheets ? Nuffield Foundation 2011 downloaded from

Copiable page 5 of 14

Fill the gaps in the table.

Percentage 10%

Fraction

3 10 40%

3 5 70%

9 10 25% 3 4

Decimal 0.2 0.5 0.8

Nuffield Free-Standing Mathematics Activity `Fractions, decimals and percentages' Student sheets ? Nuffield Foundation 2012 downloaded from

Copiable page 6 of 14

Follow me ? fractions to percentages

Set A

I am 100%

Who is

1 2

?

I am Who is

75%

1 10

?

I am Who is

30%

2 5

?

I am Who is

80%

3 5

?

I am Who is

50%

1 5

?

I am Who is

10%

1 4

?

I am Who is

40%

7 10

?

I am Who is

60%

9 10

?

I am Who is

20%

3 4

?

I am Who is

25%

3 10

?

I am Who is

70%

4 5

?

I am Who is

90%

1?

Nuffield Free-Standing Mathematics Activity `Fractions, decimals and percentages' Student sheets ? Nuffield Foundation 2012 downloaded from

Copiable page 7 of 14

Follow me ? fractions to percentages

Set B

I am 100%

Who is

1 2

?

I am Who is

50%

1 5

?

I am Who is

20%

3 4

?

I am Who is

75%

1? 10

I am Who is

10%

1 4

?

I am Who is

25%

3? 10

I am Who is

30%

2 5

?

I am Who is

40%

7? 10

I am Who is

70%

4 5

?

I am Who is

80%

3 5

?

I am Who is

60%

9 10

?

I am Who is

90%

11 20

?

I am Who is

55%

3 50

?

I am Who is I am Who is

6%

1 3

?

33

1 3

%

14 25

?

I am Who is

56%

5 8

?

I am

62

1 2

%

Who is

19 20

?

I am Who is

95%

37 50

?

I am Who is

74%

3 8

?

I am

37

1 2

%

Who is

2 25

?

Nuffield Free-Standing Mathematics Activity `Fractions, decimals and percentages' Student sheets ? Nuffield Foundation 2012 downloaded from

I am Who is

8%

7 20

?

Copiable page 8 of 14

 ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download