If an electric kettle uses
1 answer:
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
You might be interested in
Answer:
a
The decision rule is
Reject the null hypothesis
The conclusion is
There is sufficient evidence to show that there is a difference between the performances of these two models
b
The 95% confidence interval is
Step-by-step explanation:
From the question we are told that
The sample size is n = 36
The first sample mean is
The first standard deviation is
The second sample mean is
The second standard deviation is
The level of significance is
The null hypothesis is
The alternative hypothesis is
Generally the test statistics is mathematically represented as
=>
=>
From the z table the area under the normal curve to the left corresponding to 2.3 is
Generally the p-value is mathematically represented as
=>
=>
From the value obtained we see that hence
The decision rule is
Reject the null hypothesis
The conclusion is
There is sufficient evidence to show that there is a difference between the performances of these two models
Considering question b
From the question we are told the confidence level is 95% , hence the level of significance is
=>
Generally from the normal distribution table the critical value of is
Generally the margin of error is mathematically represented as
=>
=>
Generally 95% confidence interval is mathematically represented as
=>
=>