1TH/Vwo §5.3 Scale

§5.3 Scale
LEARNING GOAL:
how to calculate scale using a ratio table
1 / 27
volgende
Slide 1: Tekstslide
WiskundeMiddelbare schoolhavo, vwoLeerjaar 1

In deze les zitten 27 slides, met interactieve quizzen en tekstslides.

time-iconLesduur is: 50 min

Onderdelen in deze les

§5.3 Scale
LEARNING GOAL:
how to calculate scale using a ratio table

Slide 1 - Tekstslide

Slide 2 - Tekstslide

§5.3 Scale
HOW ?
BY MAKING RATIO TABLES FOR EVERY EXERCISE !!
JUST LIKE IN §5.1 and. §5.2
On the TEST about Ch5 this will be asked from all the time.

Slide 3 - Tekstslide

§5.3 Scale
Celebrating your birthday, inviting 300 people,
is something done ON A LARGE SCALE.



Slide 4 - Tekstslide

Vital question for 'scale':
'What does 1 cm in the drawing represent in reality?!'
This drawing could be a map of a town, a country or a 
continent,
but also the drawing of a person, an animal, or whatever.   
Let's look at a few examples!

Slide 5 - Tekstslide

Slide 6 - Tekstslide

Slide 7 - Tekstslide

Vital question for 'scale':
What does 1 cm in the drawing represent in reality?!
This drawing could be a map of a town, 
but also the drawing of an animal, or whatever.   
Let's look at an example!

Slide 8 - Tekstslide

Example of 'scale':

Slide 9 - Tekstslide

Slide 10 - Tekstslide

What is the right scale for the drawing of the weasel?
A
1 : 7.5
B
15 : 1
C
1 : 15
D
30 : 2

Slide 11 - Quizvraag

Slide 12 - Tekstslide

Slide 13 - Tekstslide

Slide 14 - Tekstslide



Scale  1 : 15  meaning   1 cm on the drawing
equals 15 cm in reality.





Slide 15 - Tekstslide

Slide 16 - Tekstslide

Homework time.
+ Later a few more slides follow!

+  CORRECT the following MISTAKE in your Paper Book:
p.185 C5a. '0.016 mm'  should be '0.016 cm' ! 

timer
15:00

Slide 17 - Tekstslide

Up to now ...
The objects (thingies) were drawn much smaller than they are in real life. However, this is going to change!
Fleas (vlooien) or ticks (teken) are seen under a microscope  or in a biology book much greater than they really are. 
In that way we can see what they really look like!

Slide 18 - Tekstslide

Slide 19 - Tekstslide


A
2 : 8
B
4 : 1
C
1 : 4
D
0.5 : 2

Slide 20 - Quizvraag

So the scale is     4 : 1  ??!
Shouldn't this result be:
1 : 4 ?
No, watch the next slide!

Slide 21 - Tekstslide

Slide 22 - Tekstslide

Did you notice this:
No  matter if the scale is about something smaller or larger than the picture, if possible we always use the number 1 !
So, not          2 : 10    but   1 : 5
However      we write      3 : 2     and  not   1 : 2/3   
No fractions or decimal numbers in a scale !
TRY ONE MORE SCALE TASK now.

Slide 23 - Tekstslide

ANS
timer
1:00

Slide 24 - Tekstslide

Solution:
1.  2.75 cm = 27.5 mm
2. 27.5 : 5.5 = 5
3. 5 mm in the drawing 
     represents 1 mm in reality, so
4.  scale is.  5 : 1

Slide 25 - Tekstslide

Slide 26 - Tekstslide

Homework time
+ Make §5.3 Scale now.

+ Good luck!

Slide 27 - Tekstslide