Solving Proportions
Tell whether the ratios form a proportion.
1/3 and 7/21
Yes
21 = 21
A car travels 12 miles in 2 hours.
What is the constant of proportionality?
k = 6 miles per 1 hour
A movie theater charges $36 for 4 tickets. Let (x) represent the number of tickets and (y) represent the total cost.
Write an equation representing the relationship.
y = 9x
Ordered Pairs
(1,2) (2,4)(3,6)(4,8)Yes
They would create a straight line through the origin.
Also, there's a C.O.P of 2
Tell whether the ratios form a proportion.
12/10 and 14/12
140 does not equal 144
A grocery store sells 5 apples for $3.75.
What is the constant of proportionality?
A car travels 150 miles in 3 hours at a constant speed. Let (x) represent the number of hours and (y) represent the distance traveled.
Write an equation representing the relationship.
Order Pairs
(-1,-2) (0,-1) (1,0) (2,1)
No
Does not create a straight line.
Does not go through the origin (0,0)
No C.O.P
Tell whether the ratios form a proportion.
3/4 and 24/18
No
54 does not equal 96
A cyclist travels 18 miles in 1.5 hours. The distance traveled is proportional to the time spent cycling.
What is the constant of proportionality?
K = 12 miles per hour
A bakery uses 3.5 cups of flour to make 2 batches of muffins. Let (x) represent the number of batches and (y) represent the cups of flour needed.
Write an equation representing the relationship.
y = 1.75x
Order Pairs
(3,2) (6,4) (9,6) (12,8)
Yes
They would create a straight line through the origin.
Also, there's a C.O.P of 2/3.
Tell whether the ratios form a proportion.
9/48 and 3/16
144 = 144
A printing company charges $8.40 for printing 6 posters. The total cost is proportional to the number of posters printed.
What is the constant of proportionality?
K = 1.40 dollars per poster
A printing company charges $18.75 to print 5 posters. Let (x) represent the number of posters and (y) represent the total cost.
Write an equation representing the relationship.
Ordered Pairs
(-2,0) (-1,2) (0,4) (1,6)
No
Does not create a straight line.
Does not go through the origin (0,0)
No C.O.P
Tell whether the ratios form a proportion.
2 to 4/5 and 3/4 to 3/10
3/5 = 3/5
A bakery uses 2.5 cups of flour to make 4 batches of cookies. The amount of flour is proportional to the number of batches made.
What is the constant of proportionality?
K = 0.625 cups per batch of cookies
A cyclist travels 7.5 miles in 0.5 hours at a constant speed. Let (x) represent the number of hours and (y) represent the distance traveled. Write an equation representing the relationship.
y = 15x
Ordered Pairs
(1,0.5) (3, 1.5) (5, 2.5) (7,3.5)
Yes
They would create a straight line through the origin.
Also, there's a C.O.P of 1/2