Interpreting points
Example
Four friends are represented on a graph. Look at the following statements about them.
- Sophie is the tallest
- George and Waseem are the same height
- Freda is the shortest
- George is the oldest
- Sophie and Waseem are the same age
- Freda is the youngest
Question
Match the names of the people to the letters on the graph.
First look at the two variables along the axes. In this case they show height and age.
Start by putting the four people in order of height from shortest to tallest.
In this case it will be Freda first (A), George and Waseem next equal and Sophie last (D).
Now put the ages in the correct order according to the statements in the question.
Although George and Waseem are the same height, George is older so he is C and Waseem is B.
A is Freda, B is Waseem, C is George and D is Sophie.
Question
A company uses the following charges for photocopying:
\(50\) copies or less - \(20p\) each
Extra copies - \(10p\) each
Which of the following graphs A, B or C could show how the cost changes with the number of copies?
The answer is C. Prices start off at \(20p\) per copy, so there is a steady straight line.
Charges then drop to only \(10p\), so a less steep straight line.
