Sean has 4 science fiction books for every 3 sports books. Which graph represents his book collection?

On a coordinate plane, a graph titled Book Collection has science fiction on the x-axis and sports on the y-axis. Points (3, 4) and (6, 8) are plotted.

On a coordinate plane, a graph titled Book Collection has science fiction on the x-axis and sports on the y-axis. Points (3, 5) and (6, 9) are plotted.

On a coordinate plane, a graph titled Book Collection has science fiction on the x-axis and sports on the y-axis. Points (4, 3) and (8, 6) are plotted.

On a coordinate plane, a graph titled Book Collection has science fiction on the x-axis and sports on the y-axis. Points (3, 2) and (6, 4) are plotted.

1 answer

Sean has a ratio of 4 science fiction books for every 3 sports books. This can be represented mathematically as:

\[ \frac{\text{Science Fiction}}{\text{Sports}} = \frac{4}{3} \]

This implies that for every 4 science fiction books, there will be 3 sports books. We can express this ratio as a linear equation by letting \(x\) represent the number of science fiction books and \(y\) represent the number of sports books:

\[ y = \frac{3}{4}x \]

We can test each set of points given in the options to see which fits this equation:

  1. Option 1: Points (3, 4) and (6, 8)

    • For (3, 4): \[ y = \frac{3}{4}(3) = \frac{9}{4} \text{ (not 4, so does not fit)} \]
    • For (6, 8): \[ y = \frac{3}{4}(6) = \frac{18}{4} = 4.5 \text{ (not 8, so does not fit)} \]
  2. Option 2: Points (3, 5) and (6, 9)

    • For (3, 5): \[ y = \frac{3}{4}(3) = \frac{9}{4} \text{ (not 5, so does not fit)} \]
    • For (6, 9): \[ y = \frac{3}{4}(6) = \frac{18}{4} = 4.5 \text{ (not 9, so does not fit)} \]
  3. Option 3: Points (4, 3) and (8, 6)

    • For (4, 3): \[ y = \frac{3}{4}(4) = 3 \text{ (fits)} \]
    • For (8, 6): \[ y = \frac{3}{4}(8) = 6 \text{ (fits)} \]
  4. Option 4: Points (3, 2) and (6, 4)

    • For (3, 2): \[ y = \frac{3}{4}(3) = \frac{9}{4} \text{ (not 2, so does not fit)} \]
    • For (6, 4): \[ y = \frac{3}{4}(6) = \frac{18}{4} = 4.5 \text{ (not 4, so does not fit)} \]

The only set of points that corresponds to the ratio of 4 science fiction books for every 3 sports books is Option 3: Points (4, 3) and (8, 6). Thus, this graph represents Sean's book collection.