Question 17

Explanation

Let the first profit $U_1 = a = 46{,}000$ and the increase $b = 18{,}000$

Determining Total Profit

The formula for the sum of the first $n$ terms of an arithmetic series

For $n = 12$, substitute the known values

Therefore, the total profit up to the 12th month is $\text{Rp}1{,}740{,}000$