Sara claims that the number of pages she has read in her book is proportional to the number of minutes that she has spent reading. She collects several data points to prove her claim and expresses the data points as (x, y) coordinate pairs.

Which of the following actions could Sara take to prove her claim?

A.
Place the coordinate pairs in a table and show that they do not create equivalent ratios.

B.
Use the coordinate pairs to show that an equation of the form
can be written.

C.
List out the coordinate pairs and show that each y-value is a multiple of its associated x-value.

D.
Plot the coordinate pairs on a graph and show that the points make a straight line through the origin.

1 answer

To prove her claim that the number of pages read is proportional to the number of minutes spent reading, Sara needs to demonstrate that there is a constant ratio between the two variables. The best way to do this is to show that the relationship can be expressed as a direct proportionality, which is indicated by a straight line passing through the origin when plotted on a graph.

Here's the analysis of each option provided:

A. Place the coordinate pairs in a table and show that they do not create equivalent ratios.

  • This would actually disprove her claim, as it implies that the ratios are not consistent.

B. Use the coordinate pairs to show that an equation of the form \(y = kx\) can be written.

  • This is a valid approach and supports her claim, as it directly shows the proportional relationship where \(k\) is a constant.

C. List out the coordinate pairs and show that each y-value is a multiple of its associated x-value.

  • This would also support her claim and demonstrates the proportional relationship.

D. Plot the coordinate pairs on a graph and show that the points make a straight line through the origin.

  • This is also a valid way to prove her claim, as it visually demonstrates the relationship is linear and proportional.

Therefore, the best actions for Sara to take to prove her claim would be:

B, C, and D.

Any of these choices could effectively demonstrate the proportional relationship between the pages read and the minutes spent reading.