- LPU MCA Semester 1
- PEA515
- Unit 7
PEA515 · Unit 7: Data interpretation
Bar graphs and line graphs
30 practice questions · in the ETE syllabus
Key points
- Read the values, then compute
- Percentage growth uses the earlier value as base
- Largest gap is not the same as highest value
- Profit percentage is on the cost (expenditure)
Bar and line graphs show how values change across categories or years. In an exam you read each value from the graph (here given as rows of numbers) and then apply a formula.
| Question | Method |
|---|---|
| Year with the largest gap between two series | Find the gap for every year, ignoring the sign |
| Percentage growth between two years | (later - earlier) / earlier x 100 |
| Average over the years | Total / number of years |
| Year with the highest percentage rise on the previous year | Compute each rise as a percentage of the previous year |
| Profit percentage from income and expenditure | (income - expenditure) / expenditure x 100 |
Example: exports of 150 in one year and 210 in another show a growth of 60 / 150 = 40%. The biggest absolute rise and the biggest percentage rise can be in different years, because a small base makes a small rise look large in percentage terms.
In a line graph, the slope between points shows the change, but always compute from the values rather than from the picture.
Exam trap: the highest value, the largest gap and the highest percentage rise are three different questions and often have three different answers.