Mr.Martinez is comparing the price of oranges from several different markets. Which market's pricing guide is based on a constant unit price? A.

$$\begin{matrix} \text{Number of Oranges} & \text{5} & \text{10} & \text{15} & \text{20}\\ \text{Total Cost (\$)} & \text{3.50} & \text{6.00} & \text{8.50} & \text{11.00}\\ \end{matrix}$$

B. 

$$\begin{matrix} \text{Number of Oranges} & \text{5} & \text{10} & \text{15} & \text{20}\\ \text{Total Cost (\$)} & \text{3.50} & \text{6.50} & \text{9.50} & \text{12.50}\\ \end{matrix}$$

C. 

$$\begin{matrix} \text{Number of Oranges} & \text{5} & \text{10} & \text{15} & \text{20}\\ \text{Total Cost (\$)} & \text{3.00} & \text{5.00} & \text{7.00} & \text{9.00}\\ \end{matrix}$$

D. 

$$\begin{matrix} \text{Number of Oranges} & \text{5} & \text{10} & \text{15} & \text{20}\\ \text{Total Cost (\$)} & \text{3.00} & \text{6.00} & \text{9.00} & \text{12.00}\\ \end{matrix}$$

Determine whether the cost for ordering multiple items that will be delivered is sometimes, always, or never proportional. Explain your reasoning.

Blake ran laps around the gym. His times are shown in the table. Blake is trying to decide whether the number of laps is proportional to the time. Find his mistake and correct it.

$$\begin{matrix} \text{Time (min)} & \text{1} & \text{2} & \text{3} & \text{4}\\ \text{Laps} & \text{4} & \text{6} & \text{8} & \text{10}\\ \end{matrix}$$

Find y when x = 14 if y varies directly with $x^{2}$, and y = 72 when x = 6.

Identify two additional values for x and y in a direct variation relationship where y = 11 when x = 18. x=; y=; x=; y-;

Identify two additional values for x and y in a direct variation relationship where y = 11 when x = 18. x=; y=; x=; y-;

Draw a graph on a separate sheet of grid paper to find each slope. Then record each slope and interpret its meaning. Zack completes 20 homework problems in 1 hour. Draw a graph of homework problems versus time. Find the value of the slope and interpret it in words.

Draw a graph on a separate sheet of grid paper to find each slope. Then record each slope and interpret its meaning. The Jackson family rents 6 movies each month. Draw a graph of movies rented versus time. Find the value of the slope and interpret it in words.

Fluid inclusions are microscopic volumes of fluid that are trapped in rock during rock formation. The article “Fluid Inclusion Study of Metamorphic Gold-Quartz Veins in Northwestern Nevada, U.S.A.: Characteristics of Tectonically Induced Fluid” describes the geochemical properties of fluid inclusions in several different veins in northwest Nevada. The following table presents data on the maximum salinity (% NaCl by weight) of inclusions in several rock samples from several areas.

$$\begin{matrix} \text{Area} & \text{Salinity}\\ \text{Humboldt Range} & 9.2 \quad 10.0 \quad 11.2 \quad 8.8\\ \text{Santa Rosa Range} & 5.2 \quad 6.1 \quad 8.3\\ \text{Ten Mile} & 7.9 \quad 6.7 \quad 9.5 \quad 7.3 \quad 10.4 \quad 7.0\\ \text{Antelope Range} & 6.7 \quad 8.4 \quad 9.9\\ \text{Pine Forest Range} & 10.5 \quad 16.7 \quad 17.5 \quad 15.3 \quad 20.0\\ \end{matrix}$$

Can you conclude that the salinity differs among the areas?

If y varies directly with x, write an equation for the direct variation. Then find each value. Find x when y = 14, If y = 7 when x = 8.

Frank and Allie purchased cell phone plans through different providers. Their costs for several minutes are shown. Graph each plan to determine whose plan is proportional to the number of minutes the phone is used. Explain your reasoning.

$$\begin{matrix} \text{Cell Phone Plans}\\ \text{Time (min)} & \text{Frank's Cost (\$)} & \text{Allie's Cost (\$)}\\ \text{0} & \text{0} & \text{4.00}\\ \text{3} & \text{1.50} & \text{4.50}\\ \text{6} & \text{3.00} & \text{5.00}\\ \text{Bumblebee} & \text{6.4} & \text{130}\\ \end{matrix}$$

An airplane is flying at an altitude of 4,000 feet and descends at a rate of 200 feet per minute. Determine whether the altitude is proportional to number of minutes. Explain your reasoning.

Draw a graph on a separate sheet of grid paper to find each slope. Then record each slope and interpret its meaning. Joshua swims 25 mete rs in 1 minute. Draw a graph of meters swam versus time. Find the value of the slope and interpret it in words.

Find the constant rate of change for each table.

$$\begin{matrix} \text{Minutes} & \text{1,000} & \text{1,500} & \text{2,000} & \text{2,500}\\ \text{Cost (\$)} & \text{38} & \text{53} & \text{68} & \text{83}\\ \end{matrix}$$