OFFICIAL SOLUIONRO1:
On the graph, for each year shown, the height of that year’s blue dot stands for the number of passenger cars sold that year in Nation X in thousands, as shown by the vertical scale. The year the most passenger cars were sold was the year with the highest blue dot, 1985. For that year, the blue dot is at a height indicating that about 2,900,000 cars were sold, and the trendline below it is at a height indicating that about 2,300,000 cars were sold. Thus, the number of cars sold that year was about 600,000 greater than the number indicated by the trendline.
The correct answer is 600,000.
RO2:
On the graph, the trendline slopes down from a height indicating that about 2,600,000 cars were sold in 1965 to a height indicating that about 1,900,000 cars were sold in 2010. Thus, the trend line shows a decline of about 2,600,000 − 1,900,000 = 700,000 cars sold annually over the 45 years from 1965 to 2010. Over the next 45 years from 2010 to 2055, if the trend line keeps the same slope, it will show another decline of about 700,000 cars sold annually, from about 1,900,000 in 2010 to about 1,200,000 in 2055. Thus, if the actual numbers of cars sold annually were to start closely following the trend line, about 1,200,000 cars would be sold in Nation X in 2055.
The correct answer is 1,200,000.