Question

For how many of the years shown after 1950 was there a decrease from the previous year in the number of registered cars?

• A. Nine
• B. Eight
• C. Seven
• D. Six
• E. Five

Hint:

Pay close attention to all plotted points on a graph, not just the ones with labels on the axis. The extra points are there for a reason and often contain the key to answering the question correctly, especially when the question asks about year-to-year changes.

Answer 1

Answer: (E)

Step 1: Understanding the Concept:
This question requires a careful visual inspection of the graph. We need to count the number of times the solid line (representing registered cars) moves downward from one year's data point to the next.
Step 2: Key Formula or Approach:
We will trace the solid line from left to right, starting after 1950, and count every instance where a line segment connecting two consecutive data points has a negative slope (i.e., it goes down). The graph plots several points between the 5-year markers, implying a year-by-year analysis is needed where available.
Step 3: Detailed Explanation:
- 1950-1972: The line shows a general upward trend. There are no year-over-year decreases visible in this period.
- Post-1972 dip: The graph shows a peak around 1972 and then a decline to the point at 1975. This represents at least one period of decrease. We will count this as one decrease.
- 1975-1980: The line shows a clear increase.
- 1980-1985: This segment shows multiple data points, which we can assume represent the individual years 1981, 1982, 1983, and 1984. - From 1980 to 1981: The line goes down. This is decrease number two. - From 1981 to 1982: The line goes down. This is decrease number three. - From 1982 to 1983: The line goes down. This is decrease number four. - From 1983 to 1984: The line goes down. This is decrease number five. - From 1984 to 1985: The line goes up sharply.
- In total, we have counted 5 distinct periods of decrease after 1950.
Step 4: Final Answer:
By visually inspecting the graph and counting each downward trend between consecutive data points, we find a total of five decreases.