Correct Answer - Option 4 : Rs. 105

**Given:**

Shrinesh office floor made up of 2800 marbles

Length of floor = 3 cm = 0.03 m

Breadth of floor = 5 cm = 0.05 m

**Formula used:**

Area of rectangle = length × breadth

**Calculation:**

Area of rectangle = (0.03 × 0.05) m^{2}

⇒ 0.0015 m^{2}

Now,

⇒ (0.0015 × 2800) m^{2}

⇒ 4.2 m^{2}

Cost of polishing the floor = Rs. (25 × 4.2)

⇒ Rs. 105

**∴ The cost of polishing the floor is Rs. 105**