constant of proportionality grade 7 quiz

📚 Quick Study Guide

• 🍎 The constant of proportionality represents the ratio between two directly proportional quantities, often denoted as $k$.
• ➗ If $y$ is directly proportional to $x$, then the relationship can be expressed as $y = kx$, where $k$ is the constant of proportionality.
• 📈 To find the constant of proportionality ($k$), divide $y$ by $x$: $k = \frac{y}{x}$.
• 📊 A graph representing a proportional relationship is a straight line passing through the origin (0,0).
• ✍️ In a table of values, the ratio between corresponding $y$ and $x$ values should be constant if they are directly proportional.

🤔 Practice Quiz

1. What is the constant of proportionality in the equation $y = 5x$?
   1. 0
   2. 1
   3. 5
   4. 10
2. If $y = 12$ when $x = 3$, what is the constant of proportionality?
   1. 36
   2. 9
   3. 4
   4. 15
3. Which equation represents a proportional relationship with a constant of proportionality of 2?
   1. $y = x + 2$
   2. $y = 2x$
   3. $y = x - 2$
   4. $y = \frac{x}{2}$
4. In a proportional relationship, if $x$ doubles, what happens to $y$?
   1. $y$ halves
   2. $y$ doubles
   3. $y$ remains the same
   4. $y$ becomes zero
5. The graph of a proportional relationship is:
   1. A curved line
   2. A horizontal line
   3. A vertical line
   4. A straight line passing through the origin
6. If the constant of proportionality is $\frac{1}{3}$, and $x = 9$, what is the value of $y$?
   1. 3
   2. 27
   3. 6
   4. 12
7. Which of the following tables represents a proportional relationship?

   1. x	y
      1	2
      2	3

   2. x	y
      1	3
      2	6

   3. x	y
      1	4
      2	6

   4. x	y
      1	5
      2	6