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# Calculate percentages - Convert fractions + decimal fractions into percentages

## Calculate percentages

Calculating percentages - We calculate with percentages, fractions and decimal fractions?

The percent sign: %

Percent means "out of one hundred". This means that 10 % is 10 parts out of a hundred. This gives the same description for proportions as for fractions and decimal fractions. Here we learn how to convert fractions into percentages or calculate percentages if we know the fraction or decimal fraction.

20% of the grid (20 out of 100 boxes)

30 % of the grid (30 out of 100 boxes)

50 % of the grid (50 out of 100 boxes)

100 % = the entire grid (100 boxes)

Just remember: percentages are hundredths!

• 1 % = 1 part of 100 = $$\frac {1}{100}=0.01$$
• 10 % = 10 parts of 100 = $$\frac {10}{100} = \frac {1}{10}=0,1$$
• 50 % = 50 parts of 100 = $$\frac {50}{100} =\frac {1}{2}=0.5$$

By the way: thousandths are called "per mille" (of a thousand).

To convert a fraction into a percentage, we have to expand or reduce the fraction so that the denominator of the fraction contains the number 100. The numerator then indicates the percentage!

Preliminary exercise to start: Have you understood the transformation?

Draw the correct numbers in the spaces provided!

## online exercises | percentages - fractions - decimal fractions

Exercise (1) Simple percentages - Write first as a percentage and then as a fraction!This interactive exercise is optimised for tablet and PC!

Exercise 2 (A) - simple percentages | Convert the decimals into percentages!

Exercise 2 (B) - simple percentages | Convert the fractions into percentages!

## We convert fractions into percentages

#### How to convert fractions into percentages

All fractions with a power of ten (tens 10, 100, 1000, ...) in the denominator can be written as a decimal fraction or decimal number and thus also as a percentage!

Examples:

(1) $$\frac{43}{100} =43 \%$$ therefore 43 hundredths = 43 %.

(2) $$\frac{124}{1000} =12.4 \%$$ , thus 124 thousandths = 12.4 hundredths = 12.4 %.

If there is no number of tens (power of ten) in the denominator, the following rule applies:

If you can bring the denominator of a fraction to 100 by reducing or extending it, then you can also write the fraction as a percentage.

some examples:

(1) $$\frac{3}{5} = \frac{60}{100} =60 \%$$

(2) $$\frac{1}{4} = \frac{25}{100} = 25 \%$$

Exercise 3 - Convert fractions into percentages, shorten or expand the fractions if necessary!

Worksheets Calculate Percentages

Fractions, decimals and percentages can represent the same number!

See in the example:

$$\frac{1}{4} = \frac{25}{100}=0.25 = 25 \%$$

We will deepen this connection in the next online exercise!

Exercise 4 - Complete the missing fractions | decimal fractions | percentages

Exercise 5 Percentages

Drag only the correct "True" or "False" to the right place!

Exercise 6 Percentages

Drag only the correct "True" or "False" to the right place!

Exercise 7 PercentagesDrag the right number to the right place!

Exercise 8 - Percentages | Clothing Labels

You can find the composition of the fabric on various garments. There are only the specified materials (i.e. 100 % together!) Each label is missing a percentage. Calculate the missing percentage.

## Mau-Mau card game Fractions: fractions, percentages, decimal fractions

We have already learned that a proportion can be written as a fraction, as a decimal or as a percentage.

Equal values belong together:

• Fractions as shares
• Fractions with numerator and denominator
• The number written as a decimal fraction
• The number written as a percentage

Wie in den hier gezeigten Beispielen: 1 Zehntel = $$\frac{1}{10}$$ = 0,1 = 10 %

You can print out the playing cards / flashcards for fractions here for free!

Playing Cards Learning Fractions (PDF) 4 pages

If you like the cards it would be nice if you link to this page or share the page on Facebook / Instagram!

### Instructions for playing the Mau-Mau card game Learning fractions:

Fractions - Fractions - Percentages - Decimal fractions

#### Play the card game as Mau-Mau, Mau-Mau (for 2 to 4 players):

• Shuffle the cards
• Each player receives 6 cards. If there are more than 4 players, the number is reduced accordingly.
• One card from the remaining pile is turned over, the rest of the pile remains turned over next to it.
• The youngest player starts.
• The cards may be placed on top of each other if they have the same colour or the cover sheet shows the same value, e.g. ½ = 50 % = 0.5 !
• If no card can be laid, a new card must be drawn from the deck.
• A special feature is the joker: The cards with the value 1 are considered jokers. They can always be used. The player who uses this card, the joker, is allowed to redefine the value and the colour of the current card.

#### Play the game as a quartet (with 2 to 4 players) :

• All cards are divided between the players. The aim is to collect quartets, i.e. always 4 cards that have the same value.
• Cards are taken in turn from the person next to them.
• The person who has collected the most complete quartets at the end wins.

#### Craft instructions for the playing cards - Make the cards yourself

• Print the 4 pages with the cards on cardboard or thick paper.
• Tip: When the pages are printed out, laminate them and only then cut them out! This gives the best quality.

## The book with many tasks for fractions: "Maths lesson 5 - Simple fractions".

The exercise book for getting started with fractions, with many decimal fractions tasks in one booklet!