Question

A trader earns a profit of $60000 in 1998 and a profit of $75000 in 2003. Find the average rate of change of profit.

Answer 1

Average rate of change of profit in five years that is from 1998 to 2003 is $\ 3000$ per year.

Solution:

Given that

Trader earns a profit of $\ 60000$ in 1998

Trader earns a profit of $\ 75000$ in 2003

Need to determine average rate of change of profit.

Profit earned by Trader in 1998 let us assume $\mathrm{P}_{98}=60000$

Profit earned by Trader in 2003 let us assume $\mathrm{P}_{03}=75000$

Number of years between 1998 and 2003 let say t = 2003 – 1998 = 5 years  

$\begin{aligned} \text { Average rate of change of profit } &=\frac{\text {Change in profit}}{\text {number of years}} \\\\ &=\frac{\mathrm{P}_{03}-\mathrm{P}_{98}}{t} \\\\ &=\frac{75000-60000}{5} \\\\ &=\frac{15000}{5}=3000 \end{aligned}$