Answer:
The second function represents an even function;
Step-by-step explanation:
A function f(x) is said to be even if f(x) = f(-x). All we need to do is replace x with -x in each equation, simplify it and assess whether the equation remains unchanged. If the equation is identical to the original one then it is said to be even. Another good example of an even function is the cosine function. Moreover, even functions have y-axis symmetry
Answer:
a) The mean is
b) The standard deviation is
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 zscore 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 pvalue, we get the probability that the value of the measure is greater than X.
The probability a student selected at random takes at least 55.50 minutes to complete the examination equals 0.6915.
This means that when X = 55.5, Z has a pvalue of 1 - 0.6915 = 0.3085. This means that when
So
The probability a student selected at random takes no more than 71.52 minutes to complete the examination equals 0.8997.
This means that when X = 71.52, Z has a pvalue of 0.8997. This means that when
So
Since we also have that
Question
The mean is
The standard deviation is