Question 7

Explanation

This problem can be solved using the concept of an Arithmetic Sequence, where Mr. Brikson's salary increases by a constant amount each year. We need to determine the starting term and the common difference based on the age and salary information.

Analyzing the Information

We know that this year, when Mr. Brikson is $40$ years old, his salary is $\text{Rp}15,750,000.00$. The annual salary increase (common difference) is $\text{Rp}750,000.00$.

We need to find his salary when he is $54$ years old.

Calculating the Time Difference

The first step is to calculate the time elapsed between the target age of $54$ years and the current age of $40$ years.

This implies that Mr. Brikson's salary will undergo $14$ increments.

Calculating Salary at Age $54$

The salary at age $54$ is determined by adding the accumulated increase over $14$ years to the base salary.

Let's calculate the total increase:

So the total salary becomes:

Thus, Mr. Brikson's monthly salary when he is $54$ years old will be $\text{Rp}26,250,000.00$.