Answer:
tôi không hiểu bạn nói gì
Step-by-step explanat ion :
Answer:
So about 95 percent of the observations lie between 480 and 520.
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviations of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
The mean is 500 and the standard deviation is 10.
About 95 percent of the observations lie between what two values?
From the Empirical Rule, this is from 500 - 2*10 = 480 to 500 + 2*10 = 520.
So about 95 percent of the observations lie between 480 and 520.
According to the information given in the exercise, the following expression represents the area of the rectangular garden:

And the following expression represents the combined area of the walkway around the rectangular garden and the area of the garden:

You can identify that the word "combined" indicates that that expression was obtained by adding both areas.
Knowing the above, you can set up the following equation:

Where "A" is the area of the walkway around the rectangular garden.
Solving for "A", you get the following expression:

The answer is:
Step-by-step explanation:

<h2>-20 is the right answer.</h2>
Just sayin' you shouldn't use up all ur points on one question