Here is the correct question.
The manufacturer of a smart watch claims that individuals who pay attention to how many steps they take per day will inadvertently take more steps per day than individuals who pay no attention to how many steps they take per day. To investigate this claim, the manufacturer conducts a study to estimate the difference in the mean number of steps taken by those that pay attention to how many steps they take per day and those that do not. To do so, 40 volunteers are recruited. Half of the volunteers are randomly assigned to receive a smart watch and are taught how to use it to track their steps. The other half of the volunteers are given a wristband to wear, but are not informed that the wristband is tracking their steps. The volunteers are monitored for 30 days. The mean and standard deviation of the number of steps taken per day are computed for each group. Here are the data:
Pay attention 20 10,244 1,580
Do not pay attention 20 8.,648 2,350
Which of the following is a 99% confidence interval for the difference in the mean number of steps taken by all people like these that do and do not pay attention to the number of steps they take per day using df - 19 ?
Answer:
Step-by-step explanation:
Given that :
significance level
From the Given data;
Using Excel with the function : TINV(0.01,19);
Critical value t* = 2.861
The margin of error can now be represented by the illustration:
Margin of error =
Lower Limit =
Upper Limit =
Thus; the confidence interval for the difference in the mean number of steps taken by all people like these that do and do not pay attention to the number of steps they take per day using df - 19 is:
Answer:
Step-by-step explanation:
The exponential model for growth is given by :-
, where A = initial value , r = growth rate (in decimal), x = time (in years).
Given: A= 15,500 r= 3.75% = 0.0375
The exponential model for the growth of this population will be :
hence, the required model:
The answer would be $3.2
Do ya want me to explain my answer
Answer:
3 minutes; 27 minutes; 30 minutes
Step-by-step explanation:
Let the common multiplier of the given ratios be x. So, the ratios 1: 9 : 10 will become x, 9x and 10x respectively.
Therefore,
Thus, 1 hour in the ratio 1 : 9 : 10 can be divided as:
3 minutes; 27 minutes; 30 minutes
Answer:
The equation of the line is:
Step-by-step explanation:
The equation of a line has the following format:
In which m is the slope(suppose we have two points, the slope is the change in y divided by the change in x).
b is the y-intercept(the value of x when y = 0).
In this question:
When , so
Passes through the points (0,1) and (1,2). So the slope is
The equation of the line is: