Line Graphs

Line Graphs / Line Charts:

A point-to-point graph, also called a line graph, is a pictorial rendition of data in which specific values of a function are plotted as dots on a coordinate plane. Adjacent pairs of dots are connected by straight lines. In most point-to-point graphs, the independent variable is rendered along the horizontal axis with values increasing from left to right. The dependent variable is rendered along the vertical axis with values increasing from the bottom up.


The illustration is a point-to-point graph showing the temperature in degrees Celsius as a function of the local time in a fictitious town over the 24-hour period representing a hypothetical midsummer day. Temperature readings, accurate to the nearest degree, are taken at 0000 hours (midnight), 0300 hours (3:00 a.m.), 0600 hours (6:00 a.m.), 0900 hours (9:00 a.m.) and so on at 3-hour intervals until the following midnight. The results are plotted as points. Finally, each adjacent pair of points is connected by a solid, straight line segment.

Point-to-point graphs are commonly used for portraying functions in which time is the independent variable. A point-to-point graph may be superimposed on a bar graph in a specialized plot called a Pareto chart . Some point-to-point graphs allow plotting of functions having multiple dependent variables, positive/negative variables and multi-category variables.

Directions for question 1-5:

The following Line chart gives the ratio of the amounts of imports by a Company to the amount of exports from that Company over the period from 1995 to 2001. Answer the following questions based on following Line graph.




In how many of the given years were the exports more than imports ?


If the imports of a company in 1996 was Rs. 272 crores, the exports from the company in 1996 was:


What was the percentage increase in imports from 1997 to 1998 ?


If the imports in 1998 was Rs. 250 crores and the total exports in years 1998 and 1999 together was Rs 500 crores, then the imports in 1999 was :