Question

A line graph on a graph sheet shows the revenue for each year from 1990 through 1998 by points and joins the successive points by straight line segments. The point for revenue of 1990 is labelled A, that for 1991 as B, and that for 1992 as C. What is the ratio of growth in revenue between 91-92 and 90-91?
Statement A
A. The angle between AB and X-axis when measured with a protractor is 40 degrees, and the angle between CB and X-axis is 80 degrees.
Statement B
B. The scale of Y-axis is 1 cm = 1000 Rs.

• A. The question can be answered by one of the statements alone but not by the other.
• B. The question can be answered by using either statement alone.
• C. The question can be answered by using both the statements together, but cannot be answered by using either statement alone.
• D. The question cannot be answered even by using both statements together.

Hint:

To calculate growth rates from a graph, always ensure you have both the angle and scale to make the necessary unit conversions.

Answer 1

The Correct Option is C

From Statement A: The angles between the line segments and the X-axis give us some insight into the rate of change, but they alone do not provide enough information to calculate the ratio of growth.
From Statement B: The scale of the Y-axis helps us convert the graph units into actual revenue values, but we still need the rate of change between the two years, which requires combining the angle data.
Combining both statements allows us to determine the growth rates between the two periods by calculating the slopes using the given angles and scale, making the Correct Answer (3).