Question

You have a 100 W lightbulb on your front porch that is turned on 10 hours every night. If the cost of electricity is 12 cents per kilowatt-hour, how much does that lightbulb add to your monthly electric bill?

A) $0.10
B) $0.12
C) $1.20
D) $12.00

Answer 1

The 100 W lightbulb on your front porch adds a cost of $0.12 to your monthly electric bill. Option B is correct.

Step-by-step explanation:

To calculate the total cost of the 100 W lightbulb on your front porch, we need to consider the power consumed by the bulb and the duration it is turned on. The power consumed by the bulb is 100 watts, and it is turned on for 10 hours every night. So, the energy consumed by the bulb is 100 watts x 10 hours = 1000 watt-hours, or 1 kilowatt-hour (kWh).

Given that the cost of electricity is 12 cents per kilowatt-hour, we can calculate the cost of the lightbulb by multiplying the energy consumed (1 kWh) by the cost per kilowatt-hour ($0.12). Therefore, the total cost of the lightbulb on your monthly electric bill would be $0.12.