Percents &
Proportions
Proportions
A snowstorm leaves 12 inches of snow. If 20% melts,what percent remains?
Answer: 80%
Solve: 6b + 12 = 102
Answer: b = 15
What is the formula for the area of a circle?
Answer: A = πr²
Formula for volume of a cylinder?
Answer: V = πr²h
Which graph shows median, quartiles, and range?
Answer: Box-and-whisker plot
An account grows by 3.4% annually. What multiplierrepresents the growth?
Answer: 1.034
Solve: 0.5(x + 7) + 9 = 43
Answer: x = 61
A circle has diameter 8 cm. What is its radius?
Answer: 4 cm
Formula for volume of a cone?
Answer: V = ⅓πr²h
Probability of drawing a blue marble from 2 blue and 3 yellow?
Answer: 2/5
A car decreases from $12,500 to $9,875. What is thepercent decrease?
Answer: 21%
Simplify: -p(q + r + 5)
Answer: -pq − pr − 5p
Estimate the area of a circle with radius 5.
Answer: About 79–80 square units
Formula for volume of a sphere?
Answer: V = ⁴⁄₃πr³
Probability of drawing two blue marbles without replacement?
Answer: 1/10
A $195 item has $11.70 sales tax. What is the tax rate?
Answer: 6%
What type of equation has no solution?
Answer: An equation that simplifies to a false statement
If a circle's circumference is 7π, what is its diameter?
Answer: 7 units
Cylinder volume compared to same cone?
Answer: 3 times larger
What measure describes the spread of data?
Answer: Range
What is the formula for percent error?
Answer: (Error ÷ Actual Value) × 100
What type of equation models Mr.G's coffee usage?
Answer: Linear equation
What theorem helps find the diagonal of a rectangle?
Answer: Pythagorean Theorem
What is surface area?
Answer: Total area of all faces
What is a line of best fit used for?
Answer: Model trends and make predictions