1. Where the extreme meets the means
Proportions
Where the extreme meets the means

2. What is it for?

3. What is it?

4. Extremes and Means

5. Cross product

6. Is this a true proportion?

7. Another way to tell if it is a true proportion
Both rates and ratios must be equivalent
Are these 2 ratios proportional?
7:6= 21:18
Yes
Both share a factor of 3

8. Homework
Pg 120#1,2

9. Answers pg 120 1) a)yes b)yes c)no d)no e)no f)no
2) No, since 2.75/12=0.23/unit
B) yes, both cases she walking at 22.5min/km
C) yes, since both cases, jeans car burns 35L/week
D) No, since 1/9.25=0.11 and 21/89.25=0.24

10. Answers cont…
No, since cost per player is not the same(17$ and 14.96$)
Yes, in both cases admission is 8.75$/person

11. Solving proportional situations
Mass(kg)
2.5 …
7.5
Price($)
6.45 ?

12. Solving proportional situations

13. Solving proportional situation
Unit rate method
Find the missing value using a rate or ratio that is already known.
1)Pick any rate that is already there.
2)Put it into a proportion with the with rate that has missing information
Mass(kg) 1 4 11
Price($)
3.85
15.40 ?

14. Solving proportional situations

15. Solving proportional situations

16. Lets try

17. Homework
Pg 130
#1,,3,4,5

18. Answers pg 130 1) A) 21 b) 15 c) 1 D) 88 e) 36 f) 9
2. No, because Henri will be same height at 48
B) yes, because 7/3=?/5
C) No, you cannot predict speed 2min after start of race.
D) yes, 8/1=42.195/?
E) No, because 5 sugar maples will reach full maturity at same time, age 40

19. Pg 130 answers 3) a)x=33,y= 222 b) x=10.4 y=3.57 c)x=10, y= -39, -221
D) x=0,2.1, y=36
4) a) with 1.26L of water and 10.5g of sugar
B) ml and 20g
C) 1600ml and 5.76L

20. Pg 131 answers
5) a) le Cavalier b) 65.35$

21. Answer pg 132
7)a) 0.04g 2) 0.1g 3)0.17g
B) yes, it can lift object weighing up to 7.875g
C) kg
10) a) b) c) badminton 96, jumping rope d) bowling 47.25, dancing 31.5

22. Galieo activity