The price that is two standard deviations above the mean price is 4.90.
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean and standard deviation , the z-score of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Mean of 3.22 and a standard deviation of 0.84.
This means that
Find the price that is two standard deviations above the mean price.
This is X when Z = 2. So
The price that is two standard deviations above the mean price is 4.90.
The amplitude of y=sin(x) is 1 with a maximum of y=1 and a minimum of y=-1. It's amplitude is 1 because that is the distance the max( y=1 )is from the mid line (y=0) or the distance the min( y=-1 ) is from the mid line (y=0).
So we just need to find the distance the mid line, y=-12, and the max,y= 3, is from each other.
Using sampling concepts, it is found that the sampled is biased because only parents who attend the school's musical show are surveyed, hence they are not very likely to support the decrease, and the population proportion should be greater than the one found in the show.
<h3>How are samples classified?</h3>
Samples may be classified as:
Convenient: Drawn from a conveniently available pool.
Random: All the options into a hat and drawn some of them.
Systematic: Every kth element is taken.
Cluster: Divides population into groups, called clusters, and each element in the cluster is surveyed.
Stratified: Also divides the population into groups. Then, a equal proportion of each group is surveyed.
A sample has to take into account all aspects of the population, otherwise it is biased. In this problem, either people support the decrease, or they do not. Only people that went to the show were surveyed, that is, people who are unlikely to support the decrease, which generates bias, as the population proportion should be greater than the one found in the show.