Circles and Ratios
Approximately how much fencing is
needed to enclose a circular pond with a
diameter of 12.5 feet?
39.25 ft
Camilla buys 8 pizzas for $131.36. Each pizza cost the same amount. What is the cost of each pizza in dollars and cents?
$16.42
A recipe says to use 9 cups of flour to make 72 cookies. What is the constant of proportionality that relates the number of cookies made to the number of cups of flour used?
8
Hannah sold a brand new SUV that was listed for $40,000.
She earned a 12% commission. How much did Hannah make in commissions on the sale of the SUV?
$4,800
The table lists Daniela and Amir’s assets and liabilities.
Assets Liabilities
Type Amount Type Amount
Checking account $895 Student loans $29,560
Savings account $3670 Car loan $12,440
House $232,000 Credit card balance $3420
Stock fund $31,462 Mortgage $213,300
What is their net worth?
Daniela and Amir’s net worth is $9307.00.
If the radius of a circle is 4.5 in, what is the circumference?
28.26 inches
A pool has drained 1088 gallons of water after 2 hours. At this rate, how many gallons of water can drain from the pool in 10.5 hours?
5712 gallons of water drain from the pool in 10.5 hours.
Given a value for the input variable, x, and the output variable, y, calculate the constant of proportionality.
x = 21 and y = 6
2/7
A scale model of an aircraft carrier uses a scale in which 1 inch represents 500 feet. If the beam of the actual aircraft carrier is 200 feet, what is the length of the beam on the scale model in inches?
0.4 inches long
The table below shows Malik’s statement of his net worth. Assets are shown as positive numbers, and liabilities are shown as negative numbers. The value of Malik’s student loan obligation is not given.
Net Worth Statement
Item Value
Checking account $1500
Savings account $2500
Credit card debt 2$4500
Student loans ?
House (current value) $262,500
Car (current value) $19,500
Investments $7500
Malik’s net worth is $266,500. Based on the information in the table, what is the current value of Malik’s student loan obligation?
-$22,500
A circular marble tabletop has a diameter of 42 inches. Determine the area of the circular marble tabletop in square inches.
Use 3.14 for π. Round your answer to the
nearest whole square inch.
1,385 in2
A tin of mints has a mass of 48 grams. There are approximately 0.035 ounces in 1 gram. Determine the mass of the tin in ounces.
48 grams is approximately 1.68 ounces.
At an arcade, tickets can be purchased to
play games. The table shows the total cost
for number of tickets purchased.
Number of Tickets, x Total Cost (dollars), y
8 6.00
12 9.00
20 15.00
30 22.50
50 37.50
What is the constant of proportionality
that relates the total cost in dollars to the
number of tickets purchased?
6/8= 0.75
Michael wants to buy a new smart phone.
He finds four stores selling the smart
phone he wants. The deals at each store
are shown.
• Store A: 20% off of the $1000 price
• Store B: 25% off of the $850 price
• Store C: $900 price with a $150 rebate
• Store D: $800 price with a coupon for
$200 off
At which store should Michael buy his new
smart phone?
Store D
William invested $2500 in an account paying 3.5% simple interest. How much was his account worth after 5 years?
$2,937.50
What is pi?
A.The circumference divided by the area of the circle
B.The area to the circumference
C.The circumference divided by the diameter
D.The circumference divided by the radius
C.the circumference divided by the diameter
The distance between two lighthouses is 137 miles. There are approximately 8 kilometers in 5 miles. Which measurement is closest to the number of kilometers between these two lighthouses?
219.2 km
The weight of a person on Venus is directly proportional to their weight on Earth. A person weighing 120 pounds on Earth weighs 106 pounds on Venus.
Approximately how much would a person weighing 180 pounds on Earth weigh on Venus?
159 pounds
A map uses a scale in which 3 inches represents 450 miles. The actual distance between two cities is 1350 miles. What is the distance between the same two cities on the map in inches?
9 inches
The Chen family has created a list of anticipated monthly expenses.
Category Amount
Mortgage payment $1140
Property tax $360
Utility Bills $225
Food $600
Transportation $300
Entertainment $180
Emergencies $195
Determine the percent of the monthly expenses represented by entertainment and transportation.
16%
Diego wants to buy a cover for the top of his circular pool, but he doesn’t know the area. When the diameter of the pool is 20 feet, what is the area of the pool?
Use 3.14 for p. Show or explain your reasoning.
315
A copier prints 48 black-and-white pages in 1.5 minutes. The same copier prints 20 color pages in 2.5 minutes.
What are the rates in pages per minute for black-and-white and color printing?
32 pages per minute for black and white copies
8 pages per minute for color copies
A recipe for apple muffins calls for 3 cups of flour to make 24 muffins. The graph shows the cups of flour needed for different amounts of muffins.
What is the constant of proportionality that relates the number of muffins to the number of cups of flour used?
8
Amir used a coupon to buy new shoes. The original cost of the shoes was $124. After using his coupon, the new cost of the shoes before tax was $86.80. What percent did Amir’s coupon take off the original price? Show your work.
30% off
Ana deposited $2000 in a retirement account that offers 5% interest compounded annually. She makes no additional deposits or withdrawals. Which amount is closest to the interest Ana earned at the end of 2 years?
$205