Ratios and Proportional Relationships
Ratios and Proportional Relationships 7.RP
Analyze proportional relationships and use them to solve real-world
and mathematical problems.
1. Compute unit rates associated with ratios of fractions, including ratios
of lengths, areas and other quantities measured in like or different
units. For example, if a person walks 1/2 mile in each 1/4 hour, compute
the unit rate as the complex fraction 1/2/1/4 miles per hour, equivalently 2
miles per hour.
2. Recognize and represent proportional relationships between
quantities.
a. Decide whether two quantities are in a proportional relationship,
e.g., by testing for equivalent ratios in a table or graphing on a
coordinate plane and observing whether the graph is a straight
line through the origin.
b. Identify the constant of proportionality (unit rate) in tables,
graphs, equations, diagrams, and verbal descriptions of
proportional relationships.
c. Represent proportional relationships by equations. For example, if
total cost t is proportional to the number n of items purchased at
a constant price p, the relationship between the total cost and the
number of items can be expressed as t = pn.
d. Explain what a point (x, y) on the graph of a proportional
relationship means in terms of the situation, with special attention
to the points (0, 0) and (1, r) where r is the unit rate.
3. Use proportional relationships to solve multistep ratio and percent
problems. Examples: simple interest, tax, markups and markdowns,
gratuities and commissions, fees, percent increase and decrease, percent
error.
Ratios and Proportional Relationships 7.RP
Analyze proportional relationships and use them to solve real-world
and mathematical problems.
1. Compute unit rates associated with ratios of fractions, including ratios
of lengths, areas and other quantities measured in like or different
units. For example, if a person walks 1/2 mile in each 1/4 hour, compute
the unit rate as the complex fraction 1/2/1/4 miles per hour, equivalently 2
miles per hour.
2. Recognize and represent proportional relationships between
quantities.
a. Decide whether two quantities are in a proportional relationship,
e.g., by testing for equivalent ratios in a table or graphing on a
coordinate plane and observing whether the graph is a straight
line through the origin.
b. Identify the constant of proportionality (unit rate) in tables,
graphs, equations, diagrams, and verbal descriptions of
proportional relationships.
c. Represent proportional relationships by equations. For example, if
total cost t is proportional to the number n of items purchased at
a constant price p, the relationship between the total cost and the
number of items can be expressed as t = pn.
d. Explain what a point (x, y) on the graph of a proportional
relationship means in terms of the situation, with special attention
to the points (0, 0) and (1, r) where r is the unit rate.
3. Use proportional relationships to solve multistep ratio and percent
problems. Examples: simple interest, tax, markups and markdowns,
gratuities and commissions, fees, percent increase and decrease, percent
error.