Answer:
c. students who eat in the cafeteria
Step-by-step explanation:
it wouldnt help to include people who dont eat the food and therefore wont have an honest opinion about the food. They have to talk to the people who do eat the food, which are those who eat in the cafeteria
Write out the equation
4x-5y-2y+x
Add like terms
5x-7y
Enjoy!=)
The exponential distribution is:
where
The probability we want is how likely will a dvd player last more than 8 years, given it has already lasted 5 years
To find this, you use conditional probability.
where A is P(x>8) and B is P(x>5)
To find these probabilities, integrate over the distribution:
Sub into conditional probability formula:
Final Answer: Given a dvd player is more than 5 years old, the probability that it will last another 3 more years is about 54.9%
Answer:
1515 or 30? do not know?
Step-by-step explanation:
Answer:
0.13% of customers spend more than 46 minutes
Step-by-step explanation:
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.
In this problem, we have that:
What percentage of customers spend more than 46 minutes?
This is 1 subtracted by the pvalue of Z when X = 46. So
has a pvalue of 0.9987
1 - 0.9987 = 0.0013
0.13% of customers spend more than 46 minutes