¿Cuánta energía consumirá una lavadora de 1200W de potencia, si se deja conectada durante 20 horas? ¿Cuánto deberemos pagar si el coste de la energía consumida es de 0,12€/kWh?

The amount to be paid is €2.88 for the amount of power consumed

Explanation:

The first thing to do here is to convert the power consumption to kilo-watt

1 kilowatt = 1000 watt

x kilowatt = 1200 watt

x = 1200/1000 = 1.2 KW

we now convert this to kilowatt hour by multiplying the number of hours by the number of kilowatt.

That would be 20 * 1.2 = 24 KWh

Now, the charge is 0.12€/kWh

for 24 kWh, we have 24 * 0.12 = €2.88

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