The cost of electricity for using a kettle is K80.00 at a cost of K0.65 per unit (kWh). It takes 5minutes to boil water in a day and the kettle is used for 30 days. What is the power rating of the kettle?

Step 1: Calculate the total energy consumed by the kettle. The total cost of electricity for using the kettle is K80.00, and the cost per unit is K0.65 per kWh. $Total Energy (kWh) = \frac{Total Cost}{Cost per unit}$ $Total Energy (kWh) = \frac{K80.00}{K0.65/kWh}$ $Total Energy (kWh) \approx 123.0769 kWh$

Step 2: Calculate the total operating time of the kettle in hours. The kettle takes 5 minutes to boil water, and it is used for 30 days. Assuming it is used once per day: $Total Operating Time (minutes) = 5 minutes/day \times 30 days$ $Total Operating Time (minutes) = 150 minutes$ Convert the total operating time from minutes to hours: $Total Operating Time (hours) = \frac{150 minutes}{60 minutes/hour}$ $Total Operating Time (hours) = 2.5 hours$

Step 3: Calculate the power rating of the kettle. The power rating (in kW) is the total energy consumed divided by the total operating time. $Power (kW) = \frac{Total Energy (kWh)}{Total Operating Time (hours)}$ $Power (kW) = \frac{123.0769 kWh}{2.5 hours}$ $Power (kW) \approx 49.23076 kW$ Rounding to two decimal places, the power rating is $49.23 \text{ kW}$.

This matches option C.

The final answer is $\boxed{C. 49.23kW}$ That's 2 down. 3 left today — send the next one.