3Tvwo and 3Thavo §8.1 (A) and §10.1 (B)

• Wiskunde
• Middelbare school
• vwo
• Leerjaar 3

Today once more(!):

 Math A: § 8.1

  Math B: § 10.1 

As I understand that ....

§8.1 and §10.1 pose some problems for you,

you get some more time fot it!

We just take an extra lesson for these paragraphs.

USEFUL TIP:

Use the Solutionsbook, to see what is the meaning of an exercise, I'm sure you will understand much more of it! Read the Solution, close the Solutionsbook and try again, from Memory and you will Understand better, I am sure.

So this book is not for copying but for Inspiration to do it yourself!

So don't write '?' and get on with the next exercise, but take your time finding it out. 

Of course you may also ask me about a certain exercise and I will give you an explanation.

First ...

Math B pupils get some information.

Math A pupils, please follow the few coming slides too,

so that you are ready when it is your time for some instruction!

Math B § 10.1:

Perpendicular bisector

is today's treat!

Needed materials:

+ pair of compasses

+ pencil

+ geo triangle or ruler

Math B pupils ....

+   you now have a notion of today's paragraph

+ good luck working it all out!

Math A ...

Some question for you to answer are coming up!

Multiple choice question is coming up,

next slide. (in the next slide you will not see the options written out any more!)

What is a 'frequency polygon'?

A. a bar chart 

B. a kinda pie chart

C. a graph with numbers and time on the axes

D.  a table with frequencies

What is a frequency polygon?

1. a bar chart
2. a kinda pie chart
3. a graph about numbers and time
4. a table with frequencies

An example of a frequency polygon:

M.C. question, to be answered in the next slide!

If 21 pupils of 30 have a good mark,

                         How to calculate the percentage?

A. making a ratio table

B. 21/30 x 100%

C. calculate 1% of the total, then divide 21 by it.

D. use your geo triangle 

Calculating a percentage by ...

1. making a ratio table
2. first calculate 1% of the total, then divide 21 by it.
3. so 21/30 x 100 %
4. looking in my cristal ball

One way of calculating 21 pupils of 30:

Another -shorter- way:

§8.1 is about this:

Only for VWO:

A mysterious saying:

The example in the next slide makes this more clear!

Watch: From 1990 to 2017 the percentages (relative frequencies) in the first two 

columns go down.

But in the last column you see that the population (absolute frequencies) go up!

still mysterious to you?!

It won't be when you are doing §8.1 !

Make  §8.1 for yourself now.

Good luck!

Do not forget to send me pictures 

of your work.