An electric water heater consumes 2.5 kW for 1.9 h per day. What is the cost (in $) of running it for one year if electricity costs 1

Question

An electric water heater consumes 2.5 kW for 1.9 h per day.
What is the cost (in $) of running it for one year if electricity costs 11.5 cents/kWh?

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Thiên Hương 10 hours 2021-07-21T22:16:40+00:00 1 Answers 0 views 0

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    2021-07-21T22:18:25+00:00

    Answer:

    The cost of running the electric water heater for one year is 55.2391 $

    Explanation:

    The simple rule of 3 helps to quickly solve proportionality problems when you have three known values ​​and one unknown. If two quantities are directly proportional (that is, when multiplying or dividing one of them by a number, the other is multiplied or divided respectively by the same number) the rule of three can be applied as follows:

    a ⇒ b

    c ⇒ x

    So: x=\frac{c*b}{a}

    where a, b and c are the known values ​​and x is the value you want to find out.

    In this case, you can first apply the following rule of three: if 2.5 kW are consumed in 1.9 hours, in 1 hour how many kW are consumed?

    kWh=\frac{1 h*2.5 kW}{1.9 h}

    kWh=1.316

    So an electric water heater consumes 1.316 kWh in one day. You apply another simple rule of three: if the heater in 1 day consumes 1.316 kWh, in 365 days (1 year) how many kWh are consumed?

    kWh=\frac{365 days*1.316 kWh}{1 day}

    kWh= 480.34

    So an electric water heater consumes 480.34 kWh in a year.

    If 1 kWh costs 11.5 cents, 480.34 kWh how many cents does it cost?

    cost=\frac{480.34 kWh*11.5 cents}{1 kWh}

    cost= 5,523.91 cents

    Finally, if 100 cents is equal to 1 dollar, 5,523.91 cents, how many dollars are equal?

    cost=\frac{5,5523.91 cents*1 dollar}{100 cents}

    cost= 55.2391 $


    The cost of running the electric water heater for one year is 55.2391 $

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