Respuesta :
Answer:
After thirty days with the mentioned use the cost of the device is R$ 507,00.
Step-by-step explanation:
We first need to calculate its total power consumption over the 30 days. Since its turned on four times a day for 2 h and 36 min each, we need to multiply this time by 4 to have the time it's turned on in a day and multiply that by 30 to calculate its total power consumption. Although, we need to convert the time from hours and minutes to only hours, to do that we divide the minutes part by 60 and sum it on the hour part. All of this is done below:
[tex]t = 2 + \frac{36}{60} = 2.6 \text{ h}[/tex]
[tex]\text{dayly time} = 4*t = 4*2.6 = 10.4 \text{ h}[/tex]
[tex]\text{monthly time} = 30*\text{dayly time} = 30*10.4 = 312\text{ h}[/tex]
[tex]\text{total power consumption} = \text{monthly time}*6500 = 312*6500\\\text{total power consumption} = 2028000 \text{ W} = 2028 \text{ kW}[/tex]
[tex]\text{total cost} = \text{total power consumption}*0.25\\\text{total cost} = 2028*0.25\\\text{total cost} = 507[/tex]
After thirty days with the mentioned use the cost of the device is R$ 507,00.
