Answer:
C = 6.28 in.
A = 3.14 in.^2
Step-by-step explanation:
C = (pi)d
C = 3.14 * 2 in.
C = 6.28 in.
A = (pi)r^2
r = d/2 = 2 in./2 = 1 in.
A = 3.14 * (1 in.^2)
A = 3.14 in.^2
Answer:
B) A random sample may represent the population <em>is your best answer.</em>
Step-by-step explanation:
Note that the answer choice says "may", which means that it doesn't <em>always</em> represent the population. Random samples means that they ask random people, and do not have a certain rule that they have to follow (such as recipients can only be a certain race, age, etc.) and that they can ask anybody they meet. This can give not only a higher chance of a general population's opinion, but also makes sure that there is not a high chance of obtaining misleading information.
For example, a random survey would not take place at a rally, in which most of the people would believe the same thing, and would answer fairly the same for the survey. Instead, a random survey may be taken at a busy intersection during the time when most people are out. You must note that though it has the best chance of getting a <em>more accurate</em> representation, it still isn't the most accurate. For the best accuracy, <em>everyone would have to answer the survey in which the survey question would affect</em>.
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I believe the problem ask for s which is the standard
deviation. We must recall that the formula for z statistic is stated as:
z = (x – x over bar) / s
Where,
z = z statistic = 2.5
x = sample value or sample score = 102
x over bar = the sample mean or sample average = 100
s = standard deviation = unknown
Rewriting the equation in terms of s:
s = (x – x over bar) / z
Substituting the given values into the equation:
s = (102 – 100) / 2.5
s = 0.8
Therefore the standard deviation s is 0.8
Answer:
The result will be inaccurate.
Step-by-step explanation:
A landscaper wants to find the answer to the question “How much time do people in Raleigh, North Carolina, spend doing yard work in one week?”
He asks the owners of all 120 houses in a Raleigh neighborhood.
The results of such a survey can never be accurate.
Firstly, the sample is not random as the person selected all the 120 houses in the neighborhood.
Secondly, few samples do not represent a large population. The city must have many lawns and the lawns of a single area does not denote the lawns of the entire city.
So, the results will be inaccurate.
