A family uses a 1.5 kW electric iron for 2 hours daily. The cost of electricity is Rs. 8 per kilowatt‑hour. Calculate the monthly (30 days) electricity bill for using the iron.

Step-by-step solution

1. Convert the power of the iron to kilowatts: $1.5\text{kW}$ (already in kW).
2. Find daily energy consumption: ${\text{Energy}}_{\text{day}}=\text{Power}\times \text{time}=1.5\text{kW}\times 2\text{h}=3\text{kWh}$.
3. Find monthly energy consumption: ${\text{Energy}}_{\text{month}}=3\text{kWh/day}\times 30\text{days}=90\text{kWh}$.
4. Calculate cost: $\text{Cost}={\text{Energy}}_{\text{month}}\times \text{rate}=90\text{kWh}\times Rs.8/\text{kWh}=Rs.720$.
5. State the final bill amount.

Concept tested: Electrical energy consumption and cost

Published 21 August 2026 · How this solution was prepared and checked

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