Topicm34bd6fdd07377a80_1528449000663_0Topic

Calculating percent of a given number

Levelm34bd6fdd07377a80_1528449084556_0Level

Second

Core curriculumm34bd6fdd07377a80_1528449076687_0Core curriculum

V. Percentage calculations. The student:

2) calculates number a equal to p percent of the given number b.

Timingm34bd6fdd07377a80_1528449068082_0Timing

45 minutes

General objectivem34bd6fdd07377a80_1528449523725_0General objective

Doing simple calculations mentally or using the long method in more difficult examples, using these abilities in practical situations.

Specific objectivesm34bd6fdd07377a80_1528449552113_0Specific objectives

1. Calculate percent of a given number.

2. Applying calculating percent of a given number to do text exercises.

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

Learning outcomesm34bd6fdd07377a80_1528450430307_0Learning outcomes

The student:

- calculates percent of a given number,

- applies calculating percent of a given number to do text exercises.

Methodsm34bd6fdd07377a80_1528449534267_0Methods

1. Situational analysis.

2. JIGSAW.

Forms of workm34bd6fdd07377a80_1528449514617_0Forms of work

1. Work in pairs.

2. Group work.

Lesson stages

Introductionm34bd6fdd07377a80_1528450127855_0Introduction

Students revise ways of converting percentspercentspercents into fractions and how to calculate fraction of a given number.

The teacher introduces the subject of the lesson – applying these skills to calculate percent of a given number.

Procedurem34bd6fdd07377a80_1528446435040_0Procedure

Task

Students work individually, using computers. Their task is to watch the Internative illustration, that describes ways of calculating percent of a given number.

[Internative illustration]

After having completed the exercise, they present results of their observations.
- In order to calculate $p$% of the given number $a$, we need to change percent into fraction and multiply it by the number $a$.
$p$% of number $a$ is $\frac{p}{100}\cdot a$.m34bd6fdd07377a80_1527752263647_0After having completed the exercise, they present results of their observations.
- In order to calculate $p$% of the given number $a$, we need to change percent into fraction and multiply it by the number $a$.
$p$% of number $a$ is $\frac{p}{100}\cdot a$.

Students use obtained information in exercises, using the JIGSAW method.

The teacher divides students into 3 persons groups. Each member of the group gets different task from the tasks below. After solving the tasks, students gather in groups that were doing the same task. They discuss the solutions and clarify any doubts. Then, they return to the initial groups and present the solutions to other members.

Task
Calculate.m34bd6fdd07377a80_1527752256679_0Calculate.

a) 22% of the price 350 zł

b) 20% of 650 m

c) 35% of one hour

d) 15% of the mass 250 dag

Task
Calculate.

a) 105,4% of the number 12

b) $6\frac{2}{3}$% of the number 102

c) $33\frac{1}{3}$% of the number 396

Task
Do the exercise, write calculations and the answer.
A bike costs 1200 zł. If we buy it as an installment purchase, we need to pay 15% percent. What is the price of this bike as an installment purchase?

The teacher evaluates the students’ work and clarifies doubts.

An extra task:
How many times will the area of a rectangle whose sides are a and b increase if we increase one of the sides by 20% and the other by 30%.

Lesson summarym34bd6fdd07377a80_1528450119332_0Lesson summary

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

Remember:
- In order to calculate $p$% of the given number $a$, we need to change percent into fraction and multiply it by the number $a$.
$p$% of number $a$ is $\frac{p}{100}\cdot a$.m34bd6fdd07377a80_1527712094602_0Remember:
- In order to calculate $p$% of the given number $a$, we need to change percent into fraction and multiply it by the number $a$.
$p$% of number $a$ is $\frac{p}{100}\cdot a$.

Selected words and expressions used in the lesson plan

caIculating fraction of a given numbercaIculating fraction of a given numbercaIculating fraction of a given number

caIculating percent of a given numbercaIculating percent of a given numbercaIculating percent of a given number

converting fraction into percentconverting fraction into percentconverting fraction into percent

converting percent into fractionconverting percent into fractionconverting percent into fraction

percentspercentspercents