Answer :
Answer:
41.4 cents
Explanation:
The Quantity of heat used up is expressed as H = Power * Time
For Burner 1;
Power rating= 1.1kW
Time used = 20mins = (20/60)hr
Time (in hour) = 1/3 hr
H = 1.1* 1/3
H = 11/10*1/3
H = 11/30kWh
For Burner 2;
Power rating= 1.1kW
Time used = 40mins = (40/60)hr
Time (in hour) = 2/3 hr
H = 1.1* 2/3
H = 11/10*2/3
H = 22/30kWh
H = 11/15 kWh
For Burner 3;
Power rating= 1.1kW
Time used = 15mins = (15/60)hr
Time (in hour) = 1/4 hr
H = 1.1* 1/4
H = 11/10*1/4
H = 11/40kWh
For Burner 4;
Power rating= 1.1kW
Time used = 45mins = (45/60)hr
Time (in hour) = 3/4 hr
H = 1.1* 3/4
H = 11/10*3/4
H = 33/40kWh
For Oven;
Power rating= 2.5kW
Time used = 30mins = (30/60)hr
Time (in hour) = 1/2 hr
H = 2.5* 1/2
H = 25/10*1/2
H = 25/20kWh
H = 5/4 kWh
Total Quantity of energy used = 11/30+11/15+11/40+33/40+5/4
Total Quantity of energy used = (44+88+33+99+150)/120
Total Quantity of energy used = 414/120
Total Quantity of energy used = 3.45kWh
If 1kWh costs 12 cents
3.34kWh will costs (12*3.45)cents
3.34kWh will cost 41.4cents
Hence the cost of electricity used in preparing the meal is 41.4 cents