# If Canadians used 7.0 X 10 11 kW x h for 1 year and there are 35 million Canadians, what is the average use of electrical energy per person for 5 days? Show your work!

ishpiro | College Teacher | (Level 1) Educator

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We are given that all Canadians used 7*10^11 kW*h for 1 year. This is the total electrical energy used by Canadians in 1 year.

Since there are 35 million Canadians, divide this energy by the 35 million to find out the average use of one person in 1 year:

`(7*10^11 kW*h)/(35,000,000) = (70*10^10 kW*h)/(35*10^6) = 2*10^4 kW*h` , or 20,000 kW*h.

To find out the average use of one person for 1 day, divide this number by the number of days in a year, 365:

`(20,000 kW*h)/365 = 54.795 kW*h` , rounding to the nearest thousandths.

The average use of one person for 5 days is then this number multiplied by 5:

54.795 kW*h * 5 = 273.97 kW*h.

The average use of electrical energy per person in 5 days is 273.97 kW*h. If you need the answer to be in Joules, than use the conversion factors:

1 kW = 1000 W and 1 hour = 3600 seconds.

273.97 kW*h = 273.97*1000*3600 Joules = 9.86*10^8 Joules.

The average use of electrical energy per person in 5 days is 273.97 kW*h, or 9.86*10^8 Joules.