• Ratio - a comparison using division, often comparing different parts of a group. Examples: 3 cars: 1 truck, 5 oz of yellow paint to 3 oz of blue paint.

    Fraction - a type of ratio where a part of a group is compared to the total or the whole. Examples: 3 cars : 4 total vehicles, 1/4 of the vehicles are trucks.

    Rate - a type of ratio that is always part-to-part since a total cannot be found. Examples: 100 cows to 3 farms, 9 steps : 3 sec, 60 miles/ 2 hours

    Unit rate - a type of rate where one quantity is 1.  Examples: 3 steps per second, 30 miles/hr, 20 students/class.

    ratio a  

    ratio b

    RATE TABLES

    Rate tables

     

    UNIT RATE  - per 1

    Unit rates

     Scale - the consistent value you count by on a number line or axis (what space between each mark is worth)

    Coordinate graph - a graph that examines the relationship between two variables. The independent variables goes on the x-axis while the dependent variables goes on the y-axis. Each axis needs a consistent scale, but the scale does not need to be the same on the two axes. Points are placed at the intersection of values for the two variables.  Points are connected for continuous data (where there is data between points).

     

    VARIABLE – a quantity (number) that can change.

    Examples

    Non-examples

    # of people

    A person’s hair color

    # of dogs

    5 dogs

    The length of a pencil

    A pencil

    Height (in)

    How cute you are

    The length of different tables at school

    The length of a table in math class

    C = cost ($)

    $2.50

     

    Independent Variable (IV) – the variable that is in “control”. The one you need first in a situation.

     

    Dependent Variable (DV) – the variable that depends on the other.

     

    EXAMPLES:

    The Phoenix Team is charging $5 per person to get into the dance. The more students who come (IV), the more money (DV) they make. [$5$]per person is a unit rate].

    The time it takes you to run the mile in PE (DV) depends on the speed at which you run (IV).

    The length of your hair (DV) depends on the time between hair cuts (IV).

    IV DV

     variable

    Here are some strategies shared when asked to find the time it would take to walk 90m, based on average time to walk 25 m.

    90 m a

    90 m b

     

    Coordinate Graphing

    Coordinate Graph

     

    Proportion

    A way to scale a ratio or rate up or down in a proportional situation (equal rates, ratios, or fractions)

    Example:

    proportion

     

    Strategies for solving for scaled part when given a part-to-part ratio

    cats dogs

     Strategies for finding scaled parts when given a scaled total and a part-to-part ratio

    turkey ham a

    turkey ham b

    Strategies for finding scaled parts when given a scaled total and a part-to-part ratio (rounding needed)

    boy girl a

    boy girl b

    boy girl c

    Strategies for finding a percent from a part-to-part ratio

    boy girl percent

    UNIT RATE IN TABLES, GRAPHS AND EQUATIONS

    Unit rate in

    STUDENTS HAVE A DEFINITION AND EXAMPLES FOR UNIT RATE WHEN PROPORTIONAL IN THE VOCABULARY SECTION OF THEIR BINDERS.

    prop 1

    prop 2

    MODELS FOR TELLING IF A TABLE SHOWS A PROPORTIONAL RELATIONSHIP

    prop model 1

    prop model 2

    CONSTANT OF PROPORTIONALITY - the unit rate in a proportional relationship.

    If a graph is linear, but does not go through (0,0), then there is a unit rate, but not a constant of proportionality since there is no proportional relationship.