Answer:
The proportion of the family's overall yearly electricity that is attributed to running both air conditioners over the summer months is = 19.4 %
Explanation:
Monthly average electricity usage = 900 kWh
The family utilizes two window air conditioners to cool their residence during summer for three months.
The electricity usage for a single window-unit air conditioner = 350 kWh
The total power utilized by both window-unit air conditioners = 350(2) = 700 kWh
The total power consumed by two air conditioners for the summer months = 700 (3) = 2100 kWh
The annual total power consumption = 900 (12) = 10800 kWh
The percentage of the family's total annual electricity for operating the air conditioners during summer =
= 19.4 %