Year 9 Interactive Maths - Second Edition

Predictions

We use the data collected in surveys to make predictions.

Example 1

A survey was conducted using 200 randomly selected students to investigate the mode of transport to school.  The question put to each student was what mode of transport do you use more often?

• Bus?
• Car?
• Bicycle?
• Train?
• Walking?

The results were tabulated as follows:

If these results give a fair indication of how all students in the state would have answered the survey question, calculate the probability of any one student in the state using the following mode of transport the most:

a. Bus
b. Car
c. Bicycle
d. Train
e. Walking

Solution:

That is, the sum of the probabilities of all events is equal to 1.

Key Terms

prediction