Which are irrational and which are rational ?
1 answer:
You might be interested in
Answer: g(f(0)) = 2 and (f ° g)(2) = -3.
Step-by-step explanation: We are given the following two functions in the form of ordered pairs :
f = {(-2, 3), (-1, 1), (0, 0), (1,-1), (2,-3)}
g = {(-3, 1), (-1, -2), (0, 2), (2, 2), (3, 1)} .
We are to find g(f(0)) and (f ° g)(2).
We know that, for any two functions p(x) and q(x), the composition of functions is defined as
From the given information, we note that
f(0) = 0, g(0) = 2, g(2) = 2 and f(2) = -3.
So, we get
Thus, g(f(0)) = 2 and (f ° g)(2) = -3.
Answer:
Yes, it would be unusual.
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal probability distribution
Problems of normally distributed samples are 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.
If or
, the outcome X is considered unusual.
Central Limit Theorem
The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean and standard deviation
, the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean
and standard deviation
.
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
In this question, we have that:
Would it be unusual for this sample mean to be less than 19 days?
We have to find Z when X = 19. So
By the Central Limit Theorem
, so yes, the sample mean being less than 19 days would be considered an unusual outcome.