1TH/vwo §8.4 Adding and subtracting fractions

§8.4 Adding and subtracting fractions.
Fractions??!
Forgotten all about them?
Next slides show you some of those little fellas!



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Slide 1: Tekstslide
WiskundeMiddelbare schoolhavo, vwoLeerjaar 1

In deze les zitten 28 slides, met interactieve quizzen en tekstslides.

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§8.4 Adding and subtracting fractions.
Fractions??!
Forgotten all about them?
Next slides show you some of those little fellas!



Slide 1 - Tekstslide

First get organised:
-  open your Notebook and
- put a pen and pencil on your table
- next slide shows you several fractions

Slide 2 - Tekstslide

Slide 3 - Tekstslide

A fraction has a ......   and a ....... see below!
The number above is called:   the numerator ( = teller). It tells us: HOW MANY?
The number below is called:    the denominator (= noemer). It tells us the 
TOTAL of the numbers and it's also the NAME.
                       4 = numerator     and                            
                        5 = denominator
54

Slide 4 - Tekstslide




Finally don't forget to SIMPLIFY the answer, if possible!

Slide 5 - Tekstslide

Slide 6 - Tekstslide

Slide 7 - Tekstslide

Slide 8 - Tekstslide

However ..... is it always just a piece of cake?

Slide 9 - Tekstslide

Sometimes it is harder to add or subtract fractions!
That is when the ................ of the fractions are unequal!
Fill in the missing word.

Slide 10 - Woordweb



With 'common' denominators 'equal' denominators are meant!

Slide 11 - Tekstslide

Slide 12 - Tekstslide

After this example
 it's time for a joke!

Slide 13 - Tekstslide

Slide 14 - Tekstslide

1. Copy this task in your Notebook and
2. Work it out.
3. Finally key in your answer in the next slide.
4352=
timer
1:00

Slide 15 - Tekstslide

43
52
- = ....

Slide 16 - Woordweb

explanation:
the new denominator becomes         4 x 5 = 20 !
                     
                   -                     =                           -                            =   

In the next slide we are going to SIMPLIFY.  Just watch!
43
52
2015
208
207

Slide 17 - Tekstslide

Slide 18 - Tekstslide

The previous subtraction was pretty simple, but .........
......  how to add or subtract fractions like:

 3           and      6          ?

Next slide explains this.
65
43

Slide 19 - Tekstslide




By the way, did you know dogs have their maths too? 
Just watch!

Slide 20 - Tekstslide

Slide 21 - Tekstslide

The following slide ...
Asks for your complete attention, 
as it deals with tricky fraction facets!
Unequal denominators and more 
trouble...

Slide 22 - Tekstslide

Slide 23 - Tekstslide

A Task for you again!
FOTOVRAAG
1. Copy this task in your Notebook.
2. Work it out and
3. Key in your whole CALCULATION plus ANSWER in the next slide.
timer
1:30

Slide 24 - Tekstslide

5 2/3 + 7/11 = ..........

Slide 25 - Open vraag

Solution:

Slide 26 - Tekstslide

                                                         37, on p.24 is a task, that .....
.... asks for some more attention and time from you!
Do not only write down the final answer,
but just like in the examples we did together:
WORK THEM OUT, as you've just seen and done!
Good luck.

Slide 27 - Tekstslide

Homework time
Do §8.4 yourself now.
You may skip:   29, 30 and 31.


Slide 28 - Tekstslide