1. **Stating the problem:**
A person deposits money in a bank every month starting with 13000 in the first month, 14500 in the second month, 16000 in the third month, and so on, increasing by a fixed amount each month. We need to find the total amount deposited at the end of two years (24 months).
2. **Identify the sequence type:**
The deposits form an arithmetic sequence where the first term $a_1 = 13000$ and the second term $a_2 = 14500$.
3. **Find the common difference $d$:**
$$d = a_2 - a_1 = 14500 - 13000 = 1500$$
4. **Number of terms $n$:**
Since the deposits are monthly for two years, $n = 24$.
5. **Formula for the sum of an arithmetic series:**
$$S_n = \frac{n}{2} (2a_1 + (n-1)d)$$
6. **Substitute the values:**
$$S_{24} = \frac{24}{2} (2 \times 13000 + (24-1) \times 1500)$$
7. **Calculate inside the parentheses:**
$$2 \times 13000 = 26000$$
$$(24-1) = 23$$
$$23 \times 1500 = 34500$$
8. **Sum inside the parentheses:**
$$26000 + 34500 = 60500$$
9. **Calculate the total sum:**
$$S_{24} = 12 \times 60500 = 726000$$
**Final answer:**
The total amount deposited at the end of two years is **726000**.
Arithmetic Deposit 6E7937
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