Answer:
The standard error of the mean is 4.5.
Step-by-step explanation:
As we don't know the standard deviation of the population, we can estimate the standard error of the mean from the standard deviation of the sample as:
The sample is [30mins, 40 mins, 60 mins, 80 mins, 20 mins, 85 mins]. The size of the sample is n=6.
The mean of the sample is:
The standard deviation of the sample is calculated as:
Then, we can calculate the standard error of the mean as:
Answer:
Total number of milkshakes sold on Monday = 300
Number of milkshakes without whipped cream = 90
Step-by-step explanation:
Given:
Adrienne adds whipped cream to 210 milk shakes which is 70% of the total milk shakes sold.
To find the total milkshakes sold.
Solution:
Let the total number of milkshakes sold on Monday be =
Percentage of milkshakes with whipped cream added to them = 70%
Number of milk shakes with added whipped cream can be given as:
⇒
⇒
⇒ [Representing percent in fraction form]
⇒ [evaluating in decimals]
We know that the number of milkshakes with whipped cream added to them = 210.
So, we have:
Solving for
Dividing both sides by 0.7
∴
Thus, total number of milkshakes sold on Monday = 300
Number of milkshakes without whipped cream = = 90