A person makes deposits into a savings account. The deposits form an arithmetic progression. The 4th deposit is 150,000 FCFA and the 6th deposit is 250,000 FCFA. Find the first deposit and the common

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Question 17:
This is an arithmetic progression problem.

Step 1: Identify the given terms in the arithmetic progression (AP).
We are given the $4^{th}$ deposit ($a_4$) and the $6^{th}$ deposit ($a_6$).

$$a_4 = 150\,000 \text{ FCFA}$$ $$a_6 = 250\,000 \text{ FCFA}$$

Step 2: Use the formula for the $n^{th}$ term of an AP, $a_n = a_1 + (n-1)d$, where $d$ is the common difference.
For $a_4$:

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