Packet #3 Overview

Packet #3 Overview

All things Rates and Ratios

Topic Overview

Proportional Relationships

Scales Models/Drawings

Similar Figures

Percents

Simple Interest​

Ratio and Rates​

Ratio

• comparison of two quantities

• can be same or different units

• written in 3 ways ~ 2 to 3, 2:3, 2/3

Ratios

The ratio of adults to children is 2 to 5. What does this mean?

For every 2 adults, there are 5 children.

Ratios

• 2 adults, 5 children

• 4 adults, ? children

• ? adults, 50 children

Rate

• compares two quantities

• measured in different units....mi/hr, price/pound

Unit Rate

• a rate with a denominator of 1 (unit means 1)

• Ex. Shelby drove 70 miles/1 hr or 70 mph

Multiple Choice

Nyoko is having a pizza party. If two large pizzas serve 9 people, how many pizzas should she order to serve 27 guests at the party?

• 6 pizzas

• 2 pizzas

• 10 pizzas

• 8 pizzas

Multiple Choice

A quarterback throws 222 yards in 6 games. How many yards does he throw in one game if he throws the same amount in each game?

• 22 yards

• 37  yards

• 52 yards

• 73 yards

Multiple Choice

A principal needs 2 chaperones for every 25 students at the school dance. How many chaperones does he need if 225 students are expected to be at the dance?

• 16 chaperones

• 8 chaperones

• 10 chaperones

• 18  chaperones

Multiple Choice

Lusita earned $85 for 8 hours of babysitting. Avery earned $125 for 11 hours of babysitting. Are the rates equivalent? 

• Yes, they are equivalent

• No, they are not equivalent

Multiple Choice

A container has four different color balls. The ratio of blue balls to red balls is 3:7 and the ratio of green balls to yellow balls is 9:21. Are the ratios of blue balls to red balls and green balls to yellow balls equivalent?

• Yes 

• No

Proportional Relationships

Characteristics of Proportional Graphs.

• They are in the shape of a straight line.

• They start or cross at the point of origin.

Multiple Choice

Which graph is non-proportional?

• A
• B
• C
• D

Multiple Choice

Does this graph represent a proportional relationship?

• Yes
• No

Multiple Choice

Is the graph proportional or non proportional?

• proportional
• non proportional

Constant of Proportionality

Multiple Choice

Does the table represent a proportional relationship?

• Yes.
• No.

Multiple Choice

What is the constant of proportionality?

• 15
• 5
• 75
• 25

Multiple Choice

In the equation y = 14x, what is the constant of proportionality?

• y
• x
• 14
• y=14

Multiple Choice

Write an equation for this relationship.

• y=1/5x
• y=1/2x
• y=2x
• y=5x

Multiple Choice

What does the scale on the map mean?

• Every 1 in in the map equals 125 mi

• Every 125 mi in the map equals 1 in

Multiple Choice

The scale on a highway construction drawing is 0.5 inches for every 45 miles. If the drawing shows the highway is 4 inches long, how long is the actual highway

• 360 mi

• 11.25 mi

• 180 mi

• 22.5 in

Similar Figures

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What makes two figures SIMILAR?

• same shape or figure

• ratios of the lengths of their corresponding sides are equal

• corresponding angles are congruent

Same Shape

The shapes must be the same, in any direction or rotation.

The size does not matter as long as we are able to identify the proportional relationship of their measurements.

Multiple Choice

What percent is shaded

• 38%

• 1.61%

• 6.2%

• 62%

Multiple Choice

Convert 46% into a decimal

• 4.6

• 0.46

• 0.046

• 0.0046

Let's try some problems..

Use your calculator to help you!

Multiple Choice

What is 40% of 80?

First, change the percent to a decimal. Next, multiply the number by the decimal.

• 32

• .40

• 60

• 41.2

Multiple Choice

Now you try these...

What is 64% of 75?

• 117

• 48

• 85

• 56

Multiple Choice

Principal = $500
Interest rate =5%
Time = 5 years
What is the interest earned?

• 95
• 105
• 125
• 135

Multiple Choice

Emilio borrows $1200 from a bank with 8% simple interest per year.  How much will he have to pay back total in 2 years?

• $150
• $192
• $1350
• $1392

Multiple Choice

You take out a car loan. How much will you pay in total for the car, if your loan is for $8000, at a rate of 5% interest, over 3 years?

• $1,200

• $120

• $920

• $9,200