Circumference/Area
What is the formula for circumference?
pi x diameter
or 2 x pi x radius
Farenheit temperature = 9/5 (Celsius) + 32
Explain why this is or is not a proportional relationship
(answers will vary)
2 pizzas can serve 8 people.
What is the constant of proportionality?
4
If Liza sells 8 bracelets for $14, how much will she make for 20 bracelets?
$35
Solve for x:
x - 21 = 21
x = 42
What is the formula for area of a circle?
pi x radius x radius
Describe a proportional relationship
the values for one quantity are each multiplied by the same number to get the values for the other quantity.
It takes Jada 28 minutes to run 4 miles. She runs at a constant pace. What is the constant of proportionality?
7
A person is running a distance race at a constant rate. What time will they finish the race?
What are the 3 pieces of missing information
Distance
time they started
Write this fraction as a decimal:
4/5
0.8
Find the circumference if the radius is 5
(3.14 for pi)
31.4
How are proportions and ratios related?
In a proportional relationship, the ratios will all be equivalent
How do you represent the constant of proportionality using the variables x and y (in an x/y t-chart)?
y/x
A bug was sitting on the tip of propeller blade with a radius of 4m when the propeller started to rotate. The bug held on for 6 rotations before flying away. How far did the bug travel before it flew off?
(use pi in your answer- you don't need to multliply by 3.14)
48 pi
Write this fraction as a percent:
3/20
15%
Find the area if the diameter is 20
314
Which circle measurements are in a proportional relationship?
(radius, diameter, circumference, area)
radius-diameter
diameter-circumference
radius-circumference
It costs $27 for every 5 boxes of cookies. What is the unit price?
$5.40
7 cm
Solve for x:
(7/8)x = 49
x= 56
If the area of a circle is 78.5, find the radius
5
Why is the formula for the area of a circle not a proportional relationship?
Theres an exponent; you're multiplying radius x radius, not radius x constant number
x y
17 6
34 12
What is the constant of proportionality?
6/17
Elena knows that 5 servings of granola weighs 1,750 g.
Write an equation to represent the relationship between s servings and w weight.
w = 350 s
s = 1/350 w
Write an expression for the difference between the square of a number and 8 times the number
x2 - 8x