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Calculate percentages - Convert fractions + decimal fractions into percentages

Calculate percentages

Calculate percentages Tasks
With Mathefritz you can learn how to calculate percentages at

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.

100 per cent 20 30 50 per cent


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!


Decimal fractions tasks
Solve the tasks online

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

Convert percentages to fractions
Convert to percent means
the denominator of the fraction must be 100!

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!


(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!
Print Maths Fritz Worksheet PDF
Mathefritz worksheets PDF
simply print out or fill in digitally
Maths Fritz picture to colour Calculate percentages
Maths trick picture to colour
simply download!

Mixed tasks

Calculate percent : Fractions Calculate percentages Decimal fractions
Fractions, decimals and percentages
can represent the same number!

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

Clothing labels Calculate percentages Tasks

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 %

Playing card 1 tenth
Playing card with the
share 1 of 10
Fraction 1 tenth
Playing card with the
fraction 1/10
Playing card 0.1 1 tenth
Playing card with the
decimal fraction 0.1
Playing card 10 per cent
Playing card with the
percentage value 10%
Print Fraction Playing Cards
2 pages as an example of the pages to print out
Maths Fritz Worksheets PDF
Mathefritz card game Fractions
to print out and make.

Calculate percentages playing cardsYou 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.
  • Complete quartets are discarded.
  • 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! 

Maths lesson 5 - Simple fractions

Exercise book for 5th grade / 6th grade

  • Length: 60 pages, DIN A 4, stitched, b/w
  • Published: 2015
  • ISBN: 978-394186817-5
  • Price: 5,95 €
  • Available everywhere in every bookshop (orderable) or in online shops.