Topicm446181e669d79beb_1528449000663_0Topic

Applying percents in doing text exercises

Levelm446181e669d79beb_1528449084556_0Level

Second

Core curriculumm446181e669d79beb_1528449076687_0Core curriculum

VI. Equations with one unknown.

The student:

1) does text exercises using first degree equations with one unknown, including percentage calculations.

Timingm446181e669d79beb_1528449068082_0Timing

45 minutes

General objectivem446181e669d79beb_1528449523725_0General objective

Choosing a proper mathematical model to a simple situation and building it in various context, also in a practical one.

Specific objectivesm446181e669d79beb_1528449552113_0Specific objectives

1) Doing text exercises related with percentage calculations, using first degree equations with one unknown.

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

Learning outcomesm446181e669d79beb_1528450430307_0Learning outcomes

The student:

- does text exercises related with percentage calculations, using first degree equations with one unknown.

Methodsm446181e669d79beb_1528449534267_0Methods

1) Situational analysis.

2) Asking an expert.

Forms of workm446181e669d79beb_1528449514617_0Forms of work

1) Individual work.

2) Group work.

Lesson stages

Introductionm446181e669d79beb_1528450127855_0Introduction

The teacher asks three students to prepare information about applying equations in exercises about percentage concentrationpercentage concentrationpercentage concentration of a solutionsolutionsolution. Students’ task is also to learn about forms of writing down unknown and given in such exercises and presenting methods of solving them.

The teacher introduces the subject of the lesson – applying equations to do exercises with percents.

Procedurem446181e669d79beb_1528446435040_0Procedure

Students work with the method of asking the expert. The teacher divides the class into 3 groups. Each group works under the supervision of the expert. The expert is a student who was told to learn information about the subject at home.

[Slideshow]

Students work under the supervision of the expert and use computers. Their task is to observe ways of doing exercises related with percentage concentrationpercentage concentrationpercentage concentration of solutions.

Then each expert teaches their groups what they learnt at home. They can illustrate their lecture with a presentation or internet sources. Students ask questions while memorising the subject of the lesson. Each group can make a poster with most important information to sum up this part of the class.

Information to remember:

- A solution can be obtained by dissolving certain substance in water.
- Brine is solution of salt.
- Syrup is solution of sugar.
- Percentage concentration of substance – determines what percentage of the mass of the solution is the mass of substance.
- Solution is a percentage when mass of the dissolved substance is a% of the mass of the whole solution.m446181e669d79beb_1527752263647_0- A solution can be obtained by dissolving certain substance in water.
- Brine is solution of salt.
- Syrup is solution of sugar.
- Percentage concentration of substance – determines what percentage of the mass of the solution is the mass of substance.
- Solution is a percentage when mass of the dissolved substance is a% of the mass of the whole solution.

Students do exercises. The expert verifies solutions and clarifies doubts.

Task
How many dag of salt needs to be poured into 150 dag of water to obtain 30% solutionsolutionsolution?

Task
120 g of water was added to 430 g of 8% brinebrinebrine. Calculate the percentage concentrationpercentage concentrationpercentage concentration of the obtained solutionsolutionsolution.

Task
Match elements from the left column (amounts of sugar) and elements from the right column (amounts of water) in such a way that after mixing water and sugar we obtain 10% syrupsyrupsyrup.

a) 0,4 kg     2,7 kg

b) 0,3 kg     4,5 kg

c) 0,9 kg     3,6 kg

d) 0,5 kg     8,1 kg

Task
By how many percentpercentpercent is the number 5 greater than the number 2?

Experts talk about their group’s work and problems they encounter. The teacher evaluates groups’ work and chooses the group that did exercises the fasters.

An extra task
Miss Magda bought 1 kilogram of apples, 1 kilogram of pears and 1 kilogram of plums. She paid 16,50 zł for everything. Pears were 25% more expensive than apples and plums were 50% more expensive than pears. How much did apples, pears and plums cost?

Lesson summarym446181e669d79beb_1528450119332_0Lesson summary

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

- A solutionsolutionsolution can be obtained by dissolving certain substancesubstancesubstance in water.

- BrinebrineBrine is solution of salt.

- SyrupsyrupSyrup is solutionsolutionsolution of sugar.

- Percentage concentrationpercentage concentrationPercentage concentration of substance – determines what percentage of the mass of the solution is the mass of substancesubstancesubstance.

- SolutionsolutionSolution is a percentage when mass of the dissolved substance is a% of the mass of the whole solution.

Selected words and expressions used in the lesson plan

brinebrinebrine

percentpercentpercent

percentage concentrationpercentage concentrationpercentage concentration

solutionsolutionsolution

substancesubstancesubstance

syrupsyrupsyrup