Answer:
The energy used in 3.5 hours = 5.25 kilowatts
Step-by-step explanation:
Energy used by electric kettle:
kilowatts
Time taken by electric kettle:
- 1.5 hours
Electric kettle's rate in kilowatts per hour can be calculated by dividing the spent energy i.e. 2.25 kilowatts by the time taken i.e. 1.5 hours.
Therefore,
Electric kettle's rate = 2.25 kilowatts / 1.5 hour
= 1.5 kilowatts per hour
Thus, the energy used in 3.5 hours = 1.5 × 3.5
= 5.25 kilowatts
Therefore, the energy used in 3.5 hours = 5.25 kilowatts