Institution: Bangladesh Bank Exam: অফিসার (ক্যাশ ) - Sonali | Rupali | BD Krishi | Rajshahi Krishi Unnayn | Investment Corporation Of Bangladesh - ২৯. ০৩.২০১৯ ||
Topic: Arithmetic Mathematics (পাটিগণিত), Subject: Mathematics (সাধারণ গণিত)

Best Answer Explained in Below-:

To solve the problem, we need to determine how many coins of each type are present in a bag that contains one rupee, 50 paisa, and 25 paisa coins, all of equal quantity, and totals a value of TK. 35.

Let the number of each type of coin be represented as \( n \).

1. **Value Contribution**:
- The value from one rupee coins is \( 1 \times n = n \) rupees.
- The value from 50 paisa coins (equivalent to 0.50 rupees) is \( 0.5 \times n = 0.5n \) rupees.
- The value from 25 paisa coins (equivalent to 0.25 rupees) is \( 0.25 \times n = 0.25n \) rupees.

2. **Total Value Equation**:
The total value from all coins can be expressed as:
\[
n + 0.5n + 0.25n = 35 \text{ rupees}
\]
This simplifies to:
\[
(1 + 0.5 + 0.25)n = 35
\]
\[
1.75n = 35
\]
Solving for \( n \), we divide both sides by 1.75:
\[
n = \frac{35}{1.75} = 20
\]

Thus, there are 20 coins of each type. The answer is **A) 20**, confirming that with 20 coins of each denomination, the total value correctly sums to TK. 35.