Understanding Ratios
Decide if the statement is true or false: The ratio of 3 to 5 is the same as the ratio of 6 to 10.
true.
If the ratio of boys to girls in a class is 4:5, how many girls are there if there are 20 boys?
There are 25 girls.
Emma has $30.00 and spends $5.00 on lunch. How much money does she have left?
Emma has $25.00 left.
Does the point (3, 6) represent a proportional relationship?
Yes, because it can be simplified to the ratio 1:2.
What is the constant of proportionality for the equation d=2.5h?
The constant of proportionality is 2.5.
Is the statement true or false: The fraction 1/4 is proportional to 2/8?
True.
If a car travels 300 miles in 5 hours, how far will it travel in 2 hours?
It will travel 120 miles.
What does the graph of a proportional relationship look like?
It is a straight line passing through the origin.
Write an equation for a line that has a constant of proportionality of 4.
The equation is y=4x.
Solve for x: If 4/x=12/36, what is x?
12
A recipe requires 2 cups of flour for 3 servings. How much flour is needed for 9 servings?
You need 6 cups of flour.
If a line passes through the origin and has a slope of 2, what is the equation of the line?
y=2x
If the ratio of red marbles to blue marbles is 7:3, how many blue marbles are there if there are 28 red marbles?
There are 12 blue marbles.
How can you determine if 5/10 and 2/4 are proportional?
Both simplify to 1/2, confirming they are proportional.
A car's fuel efficiency is represented by the equation f=25m. What is the constant of proportionality?
K=25
How can you tell if a graph represents a proportional relationship?
If the line is straight and passes through the origin.
If a recipe requires 3 cups of sugar for 12 cookies, how much sugar is needed for 48 cookies?
You need 12 cups of sugar.
Explain how to solve 3/x=9/12
x = 4
If you walk 5 miles in 1 hour, how far will you walk in 3 hours?
You will walk 15 miles
What is the constant of proportionality if the graph shows the points (2, 4) and (5, 10)?
2