If two quantities are directly related, as one increases, the other increases. Which option best describes their relationship?

If two quantities are directly related, as one increases, the other increases. Which option best describes their relationship?

• A. One increases and the other decreases
• B. One increases while the other remains constant
• C. Both increase
• D. Both decrease

Answer: (C)

Directly related means the two quantities move in the same direction. If one goes up, the other goes up; if one goes down, the other goes down. Since increasing one quantity causes the other to increase, the description that both increase best fits. The other patterns describe opposite movement, a constant value, or one increasing while the other decreases, which don’t match the stated direct relationship. For example, hours worked and earnings rise together.

Directly related means the two quantities move in the same direction. If one goes up, the other goes up; if one goes down, the other goes down. Since increasing one quantity causes the other to increase, the description that both increase best fits. The other patterns describe opposite movement, a constant value, or one increasing while the other decreases, which don’t match the stated direct relationship. For example, hours worked and earnings rise together.