2TH 7.1 100% and more

• Wiskunde
• Middelbare school
• havo
• Leerjaar 2

Welcome

Good to see you all!

Make sure you have got your notebook, pen 

and calculator in front of you!

Ch7 Exponential growth

Exponential growth

Growth factor

Standard notation

Constant graph

Ratio tabel

Factor

Exponential formula

Rising graph

Decreasing graph

What are we gone do today?

• Explanation about 100% and more
• Work independently (worksheet in Classroom)
• Closing

What are you going to learn?

You will learn:

How to calculate in a ratio table with 

percentages higher than 100%

Calculating with percentages above 100%

 A mobile phone will cost €530 excluding VAT (btw) 

Calculate the price including 21% VAT. 

Step 1 Make a table and fill in the numbers.

€	530
%	100

Calculating with percentages above 100%

 A mobile phone will cost €530 excluding VAT (btw) 

Calculate the price including 21% VAT. 

Step 2 First go back to 1 and fill in the table on the bottom

€	530
%	100	1	121

Calculating with percentages above 100%

 A mobile phone will cost €530 excluding VAT (btw) 

Calculate the price including 21% VAT. 

Step 3 What you do on the bottom you also do above

€	530		641,30
%	100	1	121

530 : 100 x 121 = 641,3

Calculating with percentages above 100%

 A mobile phone will cost €530 excluding VAT (btw) 

Calculate the price including 21% VAT. 

Step 4 Write down your final answer

€	530		641,30
%	100	1	121

The price including VAT = 641,30

Calculating with percentages above 100%

A mobile phone costs €605 including VAT.  / costs €605 with a rise of 21%

Calculate the price excluding 21% VAT. / before the rise

Step 1 make a table and fill in the numbers

€	605
%	121

Calculating with percentages above 100%

A mobile phone costs €605 including VAT.  

Calculate the price excluding of 21% VAT.

Step 2 Calculate back to 1 to get to the number asked

€	605		500
%	121	1	100

605 : 121 x 100 = 500

Calculating with percentages above 100%

A mobile phone costs €605 including VAT.  

Calculate the price excluding of 21% VAT.

Step 3 Write down your final answer.

€	605		500
%	121	1	100

The price excluding VAT is € 500,- 

A chair costs €150 excluding VAT. Calculate the price including 21 % VAT.

Calculating with percentages above 100%

A chair costs €150 excluding VAT. 

Calculate the price including 21 % VAT. 

€	150		181,5
%	100	1	121

150 : 100 x 121 =181,5

Including VAT the price is €181,50

A table costs €500 including VAT.
Calculate the price excluding 21% VAT.

Calculating with percentages above 100%

A table costs €500 including VAT. 

Calculate the price excluding 21% VAT. 

€	500		413,22
%	121	1	100

500 : 121 x 100 =413,22

Excluding VAT the price is €413,22

Work independently

 - Go to Classroom. The worksheet shows 7 exercises. Do at least 5 of them.

 

Closing

You can calculate in a ratio table with percentage above 100%

Homework

Finish the exercises from the worksheet (see Classroom). 

We will discuss the exercises in the lesson on Tuesday.