Calculating Averages

A marine biologist is measuring the sea turtle population and records the number of turtles seen at four different locations. Her data is shown below:

Location 1 - 7

Location 2 - 5

Location 3 - 13

Location 4 - 3

What was the average number of sea turtles per location?

A pupil measures the time taken for a reaction to run to completion. He repeats the experiment five times and gets the following measurements: 17 s, 30 s, 24 s, 18 s, 26 s.

Calculate the average time taken for the reaction to finish.

The population of animals can be estimated by finding the average for a sample area, and then scaling this up to a larger area.

Conservationists want to find out the tiger population in Nagarjunsagar-Srisailam Tiger Reserve, which has an area of about 5900 km². They record the number of tigers they find in 100 km² areas and see the following numbers of tigers: 3, 2, 3, 5.

How many tigers would be estimated to live in the park?

A pupil measures the mass of the crystals formed after an experiment. He obtains the following values: 5.04 g, 4.95 g, 5.56 g, 5.07 g

Calculate the average mass of the crystals formed.

The Al Marmoom Reserve project in Dubai has an area of 40 hectares. Some pupils visit the reserve on a school trip and see two of the hectares. In the first they see six Arabian oryx and in the second they see nine. How many oryx would they expect to find in the entire reserve?