A recording artist released a compilation of songs on the Internet. The scatter plot below shows the number of downloads for her album, in the thousands, over the course of nine days.
scatter plotThe graph includes the positive x and y axes. The x axis is labeled Time in days. The y axis is labeled Number of Downloads in thousands. Nine points are plotted at approximately left-parenthesis 1 comma 5 right-parenthesis, left-parenthesis 2 comma 10 right-parenthesis, left-parenthesis 3 comma 15 right-parenthesis,left-parenthesis 4 comma 20 right-parenthesis, left-parenthesis 5 comma 25 right-parenthesis, left-parenthesis 6 comma 30 right-parenthesis,left-parenthesis 7 comma 35 right-parenthesis,left-parenthesis 8 comma 40 right-parenthesis, and left-parenthesis 9 comma 45 right-parenthesis.
If this trend continues, approximately how many thousands of downloads occurred on day 10?
A. 30
B. 40
C. 50
D. 60
We notice that the number of downloads is increasing linearly with respect to time. We can find the slope of the line using any two points on the graph:
slope $= \frac{\text{change in y}}{\text{change in x}} = \frac{45-5}{9-1} = 5$
So for every day that passes, the number of downloads increases by 5000 (since each unit on the x-axis represents one day, and each unit on the y-axis represents 1000 downloads).
Therefore, on day 10 (which is one day after day 9), the number of downloads will be approximately $45+5 = 50$ (in thousands).
Therefore, the answer is $\boxed{\textbf{(C) }50}$.