Division of the common fractions
Learning objectives
You will discover the methods of division the common fractions.
Learning effect
You convert the natural number by the common fraction.
You divide the fraction by the fraction.
You specify the reciprocal of given number.
You solve the task using the division of the fractions.
You use English to describe the method of dividing common fractions.
Today you are going to discover the method of dividing the common fractions.
Prepare two sets of cards with numbers from to . Draw two cards of the first set and make the common fractioncommon fraction of it. The letter of the first card is the numerator, the letter of the other card is the denominator of the fraction. Use the pencil as a fraction bar. Then, use the other set of the cards to make such a fraction that the product of both fractions equals .
Conclusion:
If the product of two fractions different from zero equals , they are reciprocal of one another.
Complete the table:
Number | The reciprocal of a number |
There is not the reciprocal | |
Conclusion:
The number 0 has not the reciprocal.
The reciprocal of number is .
Analyse the example below.
The cake was divided into identical parts, each of them was part of the cake. How many pieces was the cake divided into?
AnswerAnswer
Watch the slideshow. You are going to learn the method of division the natural numbernatural number by the mixed numbermixed number.

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Conclusion:
To divide the natural numbernatural number by the fraction, the number should be multiplied by the reciprocal of the fraction.
The students divide the natural numbers by the mixed numbers.
Calculate:
Conclusion:
To divide the natural numbernatural number by the mixed numbermixed number we should convert the mixed numbermixed number to the improper fraction first, then divide the natural number by the fraction.
Look at the example below:
Conclusion:
To divide the common fractioncommon fraction by the other common fractioncommon fraction we should multiply the first fraction by the reciprocal of the second one.
Calculate:
Conclusion:
When the dividend or the divisor is a mixed numbermixed number it should be converted to the improper fraction.
An extra task:
The division of given number firstly by , then by can be substituted by a fraction. Find out that fraction.
Remember:
If the product of two fractions different from zero equals , they are reciprocal of one another. To divide the natural numbernatural number by the fraction , the number should be multiplied by the reciprocal of the fraction.
To divide the natural numbernatural number by the mixed numbermixed number we should convert the mixed numbermixed number to the improper fraction first, then divide the natural numbernatural number by the fraction.
To divide the common fractioncommon fraction by the other common fractioncommon fraction we should multiply the first fraction by the reciprocal of the second one.
When dividend or divisor is a mixed numbermixed number it should be converted to the improper fraction.
Check what you have learned by doing the following tasks.
Exercises
Determine which sentences are true.
There were litres of orange juice in the jug. Ann poured the juice into identical glasses with volume of of a litre. How many glasses did she pour the juice into?
Grandmother made of litre of fruit compote. She will pour it into the jugs with volume of of litre each. How many jars should she prepare to pour all the compote into?
Indicate which pairs of expressions or words are translated correctly.
- iloraz - quotient
- odwrotność liczby - reciprocal of the number
- liczba mieszana - mixed number
- ułamek zwykły - common fraction
- liczba naturalna - reducible fraction
- mnożenie ułamka - the simplest form
- ułamek zwykły
- liczba mieszana
- reciprocal of the number
- common fraction
- odwrotność liczby
- quotient
- liczba naturalna
- iloraz
- mixed number
- natural number
Glossary
ułamek zwykły
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wymowa w języku angielskim: common fraction
ułamek nieskracalny – ułamek, którego nie można skrócić
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wymowa w języku angielskim: irreducible fraction
liczba mieszana
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wymowa w języku angielskim: mixed number
mnożenie ułamka
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wymowa w języku angielskim: multiplication of the fraction
liczba naturalna
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wymowa w języku angielskim: natural number
iloraz
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wymowa w języku angielskim: quotient
odwrotność liczby
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wymowa w języku angielskim: reciprocal of the number
ułamek nieskracalny
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wymowa w języku angielskim: irreducible fraction
najprostsza postać
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wymowa w języku angielskim: simplest form
Keywords
common fractioncommon fraction
mixed numbermixed number
natural numbernatural number
quotientquotient
reciprocal of the numberreciprocal of the number