Answer: $7.74
Step-by-step explanation:
For Brand A:
Monthly electricity cost = Electricity rate (per kilowatt-hour) × Kilowatt-hours used per month
Monthly electricity cost for Brand A = $0.18/kWh × 437 kWh
For Brand B:
Monthly electricity cost for Brand B = $0.18/kWh × 394 kWh
Now, let's calculate the monthly electricity costs for each brand:
Monthly electricity cost for Brand A = $0.18/kWh × 437 kWh = $78.66
Monthly electricity cost for Brand B = $0.18/kWh × 394 kWh = $70.92
To find the savings, we subtract the monthly electricity cost of Brand B from Brand A:
Savings = Monthly electricity cost for Brand A - Monthly electricity cost for Brand B
Savings = $78.66 - $70.92
Therefore, Ms. Lee would save $7.74 per month on electricity by choosing Brand B over Brand A.