Friday, December 3

• Objective: SWBAT • find ratios and rates• solve proportions

• Homework: Practice 4-1• Bell Work (write in simplest form)

7

6

35

30

5

3

40

24

10

9

60

54

5

4

15

123

1

42

14

3

21

24

40

Vocabulary

A comparison of two quantities by division. You can write a ratio in

different ways.

10:1510

15a to b a:b

Ratio: 903

Rate: 90 miles3 hours

Read as “90 miles per 3 hours.”

A rate is a comparison of two quantities measured in different units.

Vocabulary

A Unit rate is a rate in which the second quantity is 1.

unit rate: 30 miles,1 hour

or 30 mi/h

The ratio 903

can be simplified by dividing:

903

= 301

Vocabulary

Vocabulary

equal

12 8 72 bc

an equality of two ratios

ad bc

Examples

70.2$ 027.0$

30.1$ 026.0$

75.0$ 03.0$

50

Solving A Proportion

14 y

77 7

4

35 21

105 105do cross products

5. Solving an Algebraic Proportion

28210 x

x 19x238

)4(7)2(5 xx

7

2

5

4

xx

Write cross products

287105 xx Use the distributive property

Subtract 5x from each side

Subtract 28 from each side

x238

Divide each side by 2