Room flooring cost: The length of a rectangular room is 5.5 m and the width is 3.75 m. Calculate the total cost of paving the entire floor with slabs at the rate of Rs 800 per square metre. Show the computed area first and then apply the rate to obtain the final amount.

Introduction / Context:
This problem tests area computation of a rectangle and the application of a unit rate (cost per square metre) to find total paving/flooring cost. Such questions are common in aptitude and practical arithmetic.

Given Data / Assumptions:

• Length L = 5.5 m
• Width B = 3.75 m
• Rate = Rs 800 per sq m
• Paving covers the entire floor with no wastage considered unless stated (standard assumption).

Concept / Approach:
The area of a rectangle is A = L * B. Total cost = Area * Rate.

Step-by-Step Solution:

Verification / Alternative check:
Break width: 3.75 = 3 + 0.75. Then 5.5*3 = 16.5; 5.5*0.75 = 4.125; total area = 20.625. Rate 800 gives 20*800 = 16000 and 0.625*800 = 500, summing to 16500. Consistent.

Why Other Options Are Wrong:

• Rs.15500: Undervalues the area or rate multiplication.
• Rs.17500 / Rs.18500: Overestimates total; no support from exact area.
• Rs.16000: Uses 20 sq m instead of 20.625 sq m (rounding down).

Common Pitfalls:
Ignoring the decimal parts when multiplying, or rounding area prematurely before multiplying by the rate can shift the answer by several hundred rupees.

Final Answer:
Rs.16500