I have NOT enlarged these pictures'

1
(No Transcript)
2
I have NOT enlarged these pictures. I have
STRETCHED them. They look weird because
3
When you click on any picture, you see small
white circles around the edge.
You can then grab these and drag them to make
the picture bigger or smaller.
Normally all the circles are white, but I am now
going to colour the corners green.
4
Use the green circles and BOTH sides are enlarged
AT THE SAME TIME
However, if you grab a WHITE circle you will only
enlarge IN ONE DIRECTION.
5
Those weird pictures looked out of
PROPORTION. This is because the sides were not in
the same RATIO.
5cm
8cm
What COULD the side lengths of this picture
be? What could they NOT be?
6
Could NOT be
Could be
7
We now need to use the Ratio Rectangle when
solving problems.
Duff beer costs 2.80 per litre. I want to buy
200ml of Duff. How much will it cost?
???
2.80
200ml
1 litre (1000 ml)
8
???
2.80
200ml
1 litre (1000 ml)
OK, there MUST be a connection between 200ml and
1000ml, and it MUST be a multiplication or
division. So, if 200 x 5 1000, then 1000 5
200 So we must now do 2.80 5. This gives us
56p.
9
At a barn dance there are 2 girls for every 3
boys in each line. How many boys will be dancing
when there are 35 children dancing in total?
2 girls
TOTAL 35
TOTAL 5
3 boys