### 2-7: TEKS Practice

• 1. The amount of time Gareth spends studying and his test scores have a proportional relationship. Complete the table. • 2. Think About the Process The temperature 100 ft below sea level is 33°F. The temperature at sea level is 53°F. The temperature drops 2°F every 1,000 ft above sea level. Let x be the distance above sea level in thousands of feet. Let y be the temperature.

• a. Express the relationship between x and y with an equation.

• b. Is the relationship between x and y proportional?

• c. The temperature 5,000 ft above sea level is °F.

• d. What given information did you not use to solve this problem?

• A. The rate of change of the temperature

• B. The temperature at sea level

• C. The temperature 100 ft below sea level

• 3. The table shows a proportional relationship between x and y. Complete the table. Simplify your answers. • 4. Suppose you are waiting in a line. The time it takes for you to reach the front depends on the number of people ahead of you. This is shown in the table. Does the table show a proportional relationship? • 5. Think About the Process The number of songs on a CD and the length of the CD have a ­proportional relationship.

• a. Which operation should you use to find the ratios?

• A. Multiplication

• B. Subtraction

• C. Division

For parts (b) through (d), complete the table. • 6. Megan's father is preparing y gift bags for guests at Megan's graduation party. Her father buys 5 more gift bags than the number of guests x.

• a. Express the relationship with an equation.

y = • b. Is the relationship between x and y proportional?

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