Sup guys today in class we talked about scale and scale factors.
The first thing we did was this:
Scale : Proportional Reasoning
Image : Actual
Then we did a problem is was:
A B Aprime Bprime
1 : 7 X : 23.5
But before starting with the question Mr.Backe
explained something about where the primes should go and where they shouldn't go.
Works: A/Aprime = B/Bprime
Doesn't Work: A/Aprime = Bprime/A
Then we started on the question
1 : 7 x : 23.5
1/x = 7/23.5 so you would cross multiply the numbers so 7 multiply x equals 7x
so you would put it like this.
7x/7 = 23.5/7 then 7x/7 would cancel each other out so you would divide 23.5 by 7 and your answer will be 3.36
After we were done talking about that question we did another
2 : 3 11 : x
2/3 = 11/x so as the last question went you would multiply 2 by x which would equal 2x and 3 by 11 which would equal 33. So the format would be like this
2x/2 = 33/2
2x/2 would cancel each other out and you have to divide 33 by 2 to get your answer of 16.5.
X=16.5 Mr.Backe said it was called By Inspection.
After finishing more questions we reviewed the
mm cm dm dam hm km
mi ci di 1000 deca heca kilo
1000000 10000 m 100 10 1
Then Mr.Backe asked how many 1cm would you need to reach 10km and the answer was you would need 100000 1cm to get the 10km.
Then Class Ended.
Read 4.2 139-142
Practise: odd or even
Apply: 13-16 or 15-19
Extend: 20 and 21 or 21 and 22 (you have to do 21 for sure)
TEST ON WENSDAY ON SCALE AND SCALE FACTOR
If I got anything wrong tell me so I can fix it!!!