![Placeholder: several colourful numbers](/themes/nrich/images/nrich_small_placeholder.png)
Averages
![Placeholder: several colourful numbers](/themes/nrich/images/nrich_small_placeholder.png)
![Bat Wings](/sites/default/files/styles/medium/public/thumbnails/content-97-05-six2-icon.jpg?itok=G2yd-91Z)
problem
Bat Wings
Two students collected some data on the wingspan of bats, but each lost a measurement. Can you find the missing information?
![Placeholder: several colourful numbers](/themes/nrich/images/nrich_small_placeholder.png)
![Placeholder: several colourful numbers](/themes/nrich/images/nrich_small_placeholder.png)
problem
Average temperature
The average temperature of six cities is 5$^\circ$C. What is the average temperature when two cities are added?
![Placeholder: several colourful numbers](/themes/nrich/images/nrich_small_placeholder.png)
![Placeholder: several colourful numbers](/themes/nrich/images/nrich_small_placeholder.png)
problem
Number of arms
What is the probability that the next person you meet has an above average number of arms?
![Placeholder: several colourful numbers](/themes/nrich/images/nrich_small_placeholder.png)
![Placeholder: several colourful numbers](/themes/nrich/images/nrich_small_placeholder.png)
![Unequal Averages](/sites/default/files/styles/medium/public/thumbnails/content-id-11281-icon.png?itok=L9ubz1Li)
problem
Unequal Averages
Play around with sets of five numbers and see what you can discover about different types of average...
![Half a minute](/sites/default/files/styles/medium/public/thumbnails/content-id-10999-icon.png?itok=_JHHaVAT)