Year 10 Interactive Maths - Second Edition

Modelling Exponential Decay

Example 23

Form an exponential relation for an investment of A₀ that decreases at 12% per annum for n years.

Solution:

Let A_n be the amount after n years.

Example 24

Form an exponential relation for the population of a certain city that decreases at the rate of 7% per annum for n years.

Solution:

Example 25

Form an exponential relation for the value of a house if the value is expected to fall at 4% per annum over a period of n years.

Solution:

Key Terms

exponential decay