what is the cost to run a single 100 w light bulb for 30 days if the electric company charges $0.18 for every KW-hr?
100 * 30*24 / 1000 * 0.18 = $____
$ 400 is that correct
3 * 24 * 0.18 does not equal 400
$129.60
Is that correct
Its 12.96
To calculate the cost of running a single 100-watt light bulb for 30 days, you first need to find out the total number of kilowatt-hours (kWh) used.
Step 1: Convert watts to kilowatts.
Divide the wattage of the light bulb by 1000 to convert it to kilowatts.
100 watts ÷ 1000 = 0.1 kilowatts
Step 2: Calculate kilowatt-hours used per day.
Multiply the kilowattage (0.1 kW) by the number of hours the bulb is used per day.
Let's assume the bulb is used for 6 hours per day.
0.1 kW × 6 hours = 0.6 kWh
Step 3: Calculate kilowatt-hours used for 30 days.
Multiply the kilowatt-hours used per day (0.6 kWh) by the number of days (30).
0.6 kWh × 30 days = 18 kWh
Step 4: Calculate the total cost.
Multiply the total kWh (18 kWh) by the cost per kWh ($0.18).
18 kWh × $0.18 per kWh = $3.24
Therefore, the cost to run a single 100-watt light bulb for 30 days, with an electricity rate of $0.18 per kWh, would be approximately $3.24.