7th Grade Review Lesson

​Probability - the chance that something will occur.

Math 7 | Probability

Multiple Choice

What is the probability of the spinner landing on red?

• 5/12

• 7/12

• 5/5

• 5/10 or 1/2

Reorder

Lauren spins the spinner with 8-equal sized sections one time. Drag the tiles to arrange the events in order from least likely to most likely.

• spinning a 4 or 5

• spinning a 6

• spinning an even number

• spinning a number greater than 5

1

2

3

4

• 1
• 2
• 3
• 4

Multiple Choice

$$\Delta PQR\ is\ similar\ to\ \Delta STU$$  What side corresponds to side UT?

• PQ

• RQ

• QR

• QP

Fill in the Blank

Hannah designs and conducts a computer simulation with 20 trials and uses the data to create the relative frequency bar graph shown. The graph shows the relative frequency of the number of rolls needed in order to roll all of the different numbers on a number cube. According to the results of the simulation, what is the experimental probability that 9 or more rolls are needed to roll all of the different numbers? Express your answer as a percent.

Multiple Choice

Rectangle ABCD has been enlarged to form rectangle A’B’C’D’. What is the scale factor?

• 2

• 2.5

• 3

• 3.5

Open Ended

Exit Ticket: Triangle PRQ was enlarged to form triangle SUT. What is the scale factor?

Question #3: Find the constant from a table

Multiple Choice

What is the constant of proportionality?

• 15

• 5

• 75

• 25

Multiple Choice

Find the value of x

• x = 3

• x = 30

• x = 1/3

All Proportional Graphs ...

• have points that create a straight line

• go through the origin (0,0)

Multiple Choice

Does this graph represent a proportional relationship?

• Yes

• No

Multiple Choice

Does this graph represent a proportional relationship?

• Yes

• No

How to find the constant from a graph!

• Remember constants are like unit rates

• Unit rates: a relationship where the second quantity is ONE

• Look at the x axis (left to right), and find 1

• Then go down to the left of the graph or y axis!

• This number is your constant!

Multiple Choice

What is the constant?

• 10

• 5

• 1

• 2

All Proportional Equations ...

• use the form y = kx

• k is the constant

• EXAMPLES:

• y = 3x

• y= 1/2x

• y = 5/3x

• y=12x

Multiple Choice

Write an equation for this relationship.

• y=1/5x

• y=1/2x

• y=2x

• y=5x

Multiple Choice

Write the equation for the table given

• y = 1/3x

• y = 3x

• y = 1/2x

• x = 3y

Percent Increase and Decrease

A percentage that tells us how much a quantity went up or down, expressed as a percentage of the starting amount.

Multiple Choice

A store marks up merchandise 40% for profit. If an item costs the store $12, what is the selling price?

• $16.80

• $4.80

• $44.80

• $19

Multiple Choice

Mr. Hammer received a notice from his employer that the cost of his health insurance, every pay period, will increase by 8%. If the new cost will be $28.35, what was the original cost of his insurance?

• $26.08

• $26.25

• $26.81

• $27.27

Multiple Choice

2.) Bob got a raise, and his hourly wage increased from $12 to $15. What is the percent of change?

• 25% decrease

• 25% increase

• 20% decrease

• 20% increase

Two Step Equations

• These are equations that you can solve in two steps

• Typically, the FIRST step is to take care of any addition or subtraction

• Tyipcally, the SECOND step is to take care of any multiplication or division

• There are SOME cases where the steps may be different, but that is usually if you have exponents, parentheses, or a BIG division problem

Multiple Choice

Solve -4(3x - 6) = 48

• -6

• -2

• 2

• -12

Multiple Choice

4x + 7 = 23

• x = 16

• x = 4

• x = 9

• x = 12

Fill in the Blank

Solve. Check your answer.

$$5x+12=-13$$  

Fill in the Blank

3x + 2 = 44

x = _____

Multiple Choice

Solve  9 - 3x = 10

• x = 2/3

• x = 1/3

• x = -1/3

• x = -6 1/3

Inequalities

What is an inequality?

Match

Match the following

-7x ≥ -35

27 ≤ 5x + 4x

x – 2 < -3

19 < 4 + 3d

• -7x ≥ -35

• 27 ≤ 5x + 4x

• x – 2 < -3

• 19 < 4 + 3d

-5k + 7 + 4 - 2k

Example:

Combine ONLY what is the same variable to the SAME degree

• cannot combine x and x²

Combine Like Terms

Multiple Choice

13 - x + 5 + 5x - 19

• -6x - 1

• 4x - 11

• 4x - 1

• 4x - 7

Multiple Choice

2 + 7(2x - 2)

• 14x - 12

• 14x + 16

• -14x - 12

• 14x

Multiple Choice

Simplify the expression: 2x + 1 + 7x 

• 10x

• 10

• 9x + 1

• 9 + 1x

Multiple Choice

Simplify the expression: 7+3(1 - 2x) 

• 21 - 6x

• 10 - 2x

• 10 - 20x

• 10 - 6x

Parts of a Circle

• Radius: line segment that goes from the center to the edge of the circle (HALF the DIAMETER)

• Diameter: line segment that goes from edge to edge on a circle (TWICE the RADIUS)

• Circumference: the distance around the outside of a circle (AKA perimeter)

Area of a Circle

Calculating the area of a circle

Multiple Choice

find the area of the circle below.

• 100 cm

• 225 cm

• 9 cm

• 28.26 cm

Multiple Choice

A tire has a radius of 14 inches. What is its diameter?

• 14 inches

• 7 inches

• 28 inches

Multiple Choice

A pond has a diameter of 12 feet. What is its radius?

• 12 feet

• 6 feet

• 24 feet

Multiple Choice

The radius of the circle is 9 meters. What is the circle's circumference?

• 56.52 m

• 28.26 m

• 18 m

Multiple Choice

Serena drew a circle with a circumference of 157 centimeters. What is the approximate diameter of the circle she drew?

• 1.57 cm

• 50 cm

• 15.7 cm

• 25 cm

Multiple Choice

What is the area of this circle?

• 28.26 in²

• 56.52 in²

• 254.34 in²