Learning Intention: Students will understand that substitution into formulae is a valuable mathematical process that is useful in many real-life situations.

Success Criteria: Students will work through a series of substitution exercises and identify useful formula for converting units of measurement (eg. Celcius to Fahrenheit; ounces to grams; miles to kilometers; calories to kilojoules). Students will use the formulae to calculate the height of a person knowing the length of their femur bone.

Forensic scientists are responsible for piecing together information about crimes, such as identifying victims and perpetrators from DNA evidence, fingerprints and bones. One formula that scientists use is to calculate the height of a person(h) from the length of their thigh bone – called a femur(f) in centimeters. The formula is as follows:

height = 69.09 + 2.24 x femur OR h = 69.09 + 2.24f

Walking along the beach, your dog retrieves a human thigh bone! It is 45cm long. How tall was the person this bone belonged to?

A fellow blogger, Malyn Mawby, has written a great post about how she used the Vitruvian Man to teach a lesson incorporating ratio, percentages and algebra. Do your body parts match the ratio of the Vitruvian Man?

Use the Internet to research at least five of the following and give an example of each.

1. Calories to kilojoules
2. Miles to kilometers
3. Celcius to Fahrenheit
4. Ounces (oz) to grams
5. Pounds (lbs) to kilograms
6. Acres to hectares
7. Inches to centimeters
8. Australian dollars to British sterling
9. Feet to metres
10. Time in Hawkesdale to time in Greenwich, UK.