Topicmc358550d5520e8a9_1528449000663_0Topic

Operations on common and decimal fractions

Levelmc358550d5520e8a9_1528449084556_0Level

Second

Core curriculummc358550d5520e8a9_1528449076687_0Core curriculum

V. On common and decimal fractions. The student:

3) does simply calculations with both common and decimal fractions.

XIV. Text exercises. The student:

5) applies obtained knowledge about arithmetic and geometry, calculations skills as well as own, proper methods to do exercises set in the practical context.

Timingmc358550d5520e8a9_1528449068082_0Timing

45 minutes

General objectivemc358550d5520e8a9_1528449523725_0General objective

Reading and interpreting data presented in various forms and processing it.

Specific objectivesmc358550d5520e8a9_1528449552113_0Specific objectives

1. Doing operations on common and decimal fractions.

2. Applying operations on common and decimal fractions to do text exercises.

3. Communicating in English, developing basic mathematical, computer and scientific competences, developing learning skills.

Learning outcomesmc358550d5520e8a9_1528450430307_0Learning outcomes

The student:

- does operations on common and decimal fractions,

- applies operations on common and decimal fractions to do text exercises.

Methodsmc358550d5520e8a9_1528449534267_0Methods

1. Discussion.

2. Educational game.

Forms of workmc358550d5520e8a9_1528449514617_0Forms of work

1. Work in pairs.

2. Group work.

Lesson stages

Introductionmc358550d5520e8a9_1528450127855_0Introduction

Students revise rules of operations on common fractions and rules of operations on decimal fractions.

Proceduremc358550d5520e8a9_1528446435040_0Procedure

Students work individually using computers. Their task is to get to know the interactive illustration and think about what operation needs to be done first to be able to add common and decimal fractiondecimal fractiondecimal fraction.

[Illustration interactive]

After having completed the exercise, they draw a conclusion:

- If there are both common and decimal fractions in calculations, we need to convert them to the same form, that is convert common fractions to decimals or decimals to common fractions and then do calculations.

Discussion – students wonder if we can always convert a common fractioncommon fractioncommon fraction into a decimal and a decimal into a common fractions. They revise methods of converting fractionsconverting fractionsconverting fractions.

- A decimal fractiondecimal fractiondecimal fraction can always be converted into a common fractioncommon fractioncommon fraction by writing it using the fraction bar.
- A common, simplified fraction can be converted into a decimal only if the only divisorsdivisorsdivisors of its denominator are numbers 2 or 5.

The teacher divides the class into groups that play a board game using obtained knowledge. The game consists of four regions. On each field there are calculations and tasks to solve. Students roll the dice and stop at a chosen field. If they do the task correctly, they get points. The person with the most points in the groups gets a grade from class activity.

Region I - addition.

Tasks for 1 point.
1. Do the addition: $\frac{1}{2}+0,75$
2. Do the addition: $1,25+\frac{1}{6}$
3. Do the addition: $4\frac{2}{9}+3,7$
4. Do the addition: $5\frac{3}{10}+6,5$
Task for 2 points.
5. Mum made a drink out of 4,75 kg of plums, $3\frac{1}{8}$ kg of apples $2\frac{1}{2}$ kg of strawberries. How many kilograms of fruits did she use?

Region II - subtraction.

Tasks for 1 point.
1. Do the subtraction: $\frac{5}{6}-0,125$
2. Do the subtraction: $2\frac{2}{7}-0,6$
3. Do the subtraction: $12,05-3\frac{1}{8}$
4. Do the subtraction: $18\frac{1}{5}-0,25$
Task for 2 points.
5. Ania bought green ribbon and $4\frac{3}{4}$ m of blue ribbon. How many metres of green ribbon did she buy if together there was 8,5 m of ribbon?

Region III - multiplication.

Tasks for 1 point.
1. Do the multiplication: $\frac{4}{7}\cdot 0,28$
2. Do the multiplication: $5\frac{3}{5}\cdot 1,5$
3. Do the multiplication: $0,21\cdot 2\frac{2}{7}$
4. Do the multiplication: $92,03\cdot \frac{1}{10000}$
Task for 2 points.
5. A kilogram of pears costs 3,3 zł. How much will we pay for $\frac{1}{3}$ kg of pears?

Region IV - division.

Tasks for 1 point.
1. Do the division: $\frac{6}{25}÷0,6$
2. Do the division: $0,48÷1\frac{1}{7}$
3. Do the division: $5,5÷2\frac{3}{4}$
4. Do the division: $2\frac{1}{4}÷0,75$
Task for 2 points.
5. The area of a rectangle is 6,25 cmIndeks górny 2², and the length of one side is $2\frac{1}{2}$ cm. Calculate the length of the other side of the rectangle.

The teacher evaluates students’ work and clarifies doubts.

An extra task:

The quotientquotientquotient of two numbers is equal to $4\frac{1}{6}$, and the divisor is $2\frac{29}{30}$ smaller than the quotient. Calculate the dividend.

Lesson summarymc358550d5520e8a9_1528450119332_0Lesson summary

Students do the revision exercises. Then together they sum‑up the classes, by formulating the conclusions to memorise.

- If there are both common and decimal fractions in calculations, we need to convert them to the same form, that is convert common fractions to decimals or decimals to common fractions and then do calculations.
- A decimal fraction can always be converted into a common fraction by writing it using the fraction bar.
- A common, simplified fraction can be converted into a decimal only if the only divisors of its denominator are numbers 2 or 5.mc358550d5520e8a9_1527752263647_0- If there are both common and decimal fractions in calculations, we need to convert them to the same form, that is convert common fractions to decimals or decimals to common fractions and then do calculations.
- A decimal fraction can always be converted into a common fraction by writing it using the fraction bar.
- A common, simplified fraction can be converted into a decimal only if the only divisors of its denominator are numbers 2 or 5.

Selected words and expressions used in the lesson plan

decimal fractiondecimal fractiondecimal fraction

differencedifferencedifference

divisorsdivisorsdivisors

common fractioncommon fractioncommon fraction

converting fractionsconverting fractionsconverting fractions

operation on fractionsoperation on fractionsoperation on fractions

productproductproduct

quotientquotientquotient

result of the operationresult of the operationresult of the operation

sumsumsum