THURSDAY, DECEMBER 1ST o Please Complete warm up

and take out homework (worksheet)

o Did you write down the homework?

Warm UpWrite a rule for each sequence

using “n”1. 15, 24, 33, 222. -11, -15, -19, -24

DID YOU KNOW?!?!?For most people, the ratio of thelength of their head to their total

height is 1:7. Use proportions to testyour measurements and see if they

match this ratio.

CORNY JOKE OF THE DAY

How did the hammerhead

shark do on his quiz?

He Nailed it!

ATTENTION!Next Checkpoint is

FRIDAY

HomeworkAnswers

EquivalentRatios

Equivalent ratios • are ratios that name the same

comparison. • You can find an equivalent ratio by

multiplying or dividing both terms of a ratio by the same number.

CAN YOU MAKE TWO EQUIVALENT RATIOS?!?!

1. 4.

2. 5. 5 to 9

3. 6 : 12

12

23

412

JUMPING JACKS

Number of Jumping Jacks

Equivalent #1

Equivalent #2

Equivalent #3

Time (Seconds)

Rates

WHAT IS RATE?

RATE: compares two quantities that have different units of measure

WHAT IS RATE?

For example:Abbey charges $28 dollars for 3 hours of swimming lessons. David charges $18 dollars for 2 hours of swimming lessons. Which instructor offers a better deal?

HOW DO WE FIND IT?

Divide! Set up your Rate

Abbey: charges $28 dollars for 3 hours of swimming lessons.

Rate= = = 9.33Dollarshours

283

FIND DAVID

Who had a better deal?

Set up your RateDavid: charges _______dollars for _______ hours

of swimming lessons. Rate= = =__________Dollars

hours

YOU TRY!

An 8-ounce bag ____________chips costs $1.68. A 4-ounce bag of __________chips costs $0.88. Which is the better deal?

Example#2

The new movie “Hunger Games” is expected to draw large crowds. Several cinemas have already started making package deals for movie tickets. In your groups determine which Theater has the best

deal!

Mall of Georgia Regal Cinema

5 tickets for $112

Hollywood 24

7 tickets for $135.60

PROPORTIONS

CAN YOU FINISH THE STATEMENT?1. Basketball is to hoop as soccer ball to

____________.

2. pumpkin is to Halloween as fireworks are to ________________

3. Fish is to water as bird is to _________

These are all

PROPORTIONS!

A proportion is an equation that shows two equivalent ratios.

Read the proportion = as “two is to one as four is to two.”

21__ 4

2__= 4

2__ 8

4__= 2

1__ 6

3__=

21__ 4

2__

Reading Math

CROSS PRODUCTSCross products in proportions are equal

35__ 9

15___=4

8__ 2

4__= 9

6__ 3

2__= 14

7 __ 2

1__=

8 • 2 = 4 • 4 5 • 9 = 3 • 1516 = 16 45 = 45

6 • 3 = 9 • 218 = 18

7 • 2 = 14 • 114 = 14

This is how you prove proportions!

QUESTION OF THE DAYHow would you find the missing value to

complete proportion

56 18

n

METHOD #1 Criss Cross and algebra

Cross Multiply and Divide

STEPS1. Cross multiply2. Set up equation3. Use inverse operations

to solve for missing variable

56 18

n

Criss-Cross and Solve! Find the missing value in the proportion.

6n 6

___

56__ n

18 __= Find the cross products.

6 • n = 5 • 18 The cross products are equal.

6n = 90 n is multiplied by 6.

90 6

___= Divide both sides by 6 to undo the multiplication.

n = 15

CrossMultiply

And Divide!!!!

METHOD #2

Use guess and checkCaution: doesn’t work if the answer is a fraction!

Soooooooooooo

easyyyyyyyyyyy

56 18

n

YOU TRY #1

17 21

p

YOU TRY #2

315 30

r

YOU TRY #3

129 2

n

YOU TRY #4

6 207 a

YOU TRY #5

36 4

x

REAL WORLD APPLICATION

According to the label, 1 tablespoon of plant fertilizer should be used per 6 gallons of water. How many tablespoons of fertilizer would you

use for 4 gallons of water?

f4 gal

____1 tbsp 6 gal

_____ = Let f be the amount of fertilizer for 4 gallons of water.

f4 gal

____1 tbsp 6 gal

_____ = Write a proportion.

6 • f = 1 • 4 The cross products are equal.

Continued

f is multiplied by 6.

Divide both sides by 6 to undo the multiplication.

Write your answer in simplest form.

6f = 4

6f 6

___ 4 6

__=

f = tbsp 2 3

__

You would use tbsp of fertilizer for 4 gallons of water.

2 3

__

In a proportion, the units must be in the same order in both ratios.

Caution!

tbspgal

___tbspgal

___ =

galtbsp

___galtbsp

___ =or

WHAT DID RUDOLPH DO WRONG?Fives pounds of sugar cookies cost $20 dollars, but he only

needs 3 pounds

5$20 3lbs x

lbs