Answer:
mean = 1 power failure
variance = 1 (power failure)²
Step-by-step explanation:
Since the mean is computed as
mean = E(x) = ∑ x * p(x) for all x
then for the random variable x=power failures , we have
mean = ∑ x * p(x) = 0 * 0.4 + 1* 0.3 + 2*0.2 + 3* 0.1 = 1 power failure
since the variance can be calculated through
variance = ∑[x-E(x)]² * p(x) for all x
but easily in this way
variance = E(x²) - [E(x)]² , then
E(x²) = ∑ x² * p(x) = 0² * 0.4 + 1²* 0.3 + 2²*0.2 + 3²* 0.1 = 2 power failure²
then
variance = 2 power failure² - (1 power failure)² = 1 power failure²
therefore
mean = 1 power failure
variance = 1 power failure²
These are three solutions
(0,-2)
(1,3)
(2,8)
Answer:
recently. The dollar amount collected was $835. Adult tickets, A sold for $8 each and childrens tickets, C sold - 119… ... Adult tickets, A sold for $8 each and childrens tickets, C sold for $5 each. Write a system of ... Now, we need to know how many tickets were sold from both adults and children. Our new ...
1 answer
Step-by-step explanation:
Answer:
Since the p value is lower than the significance level given of 0.05 we have enough evidence to reject the null hypothesis on this case. And the best conclusion for this case is:
We (reject) the null hypothesis. That means that we (found) evidence to support the alternative.
Step-by-step explanation:
We have the following info given:
represent the sampel mean for the age of customers
represent the population standard deviation
represent the sample size selected
We want to test if the mean age of her customers is over 35 so then the system of hypothesis for this case are:
Null hypothesis: 
Alternative hypothesis 
The statistic for this case is given by:
And replacing the data given we got:
We can calculate the p value since we are conducting a right tailed test like this:
Since the p value is lower than the significance level given of 0.05 we have enough evidence to reject the null hypothesis on this case. And the best conclusion for this case is:
We (reject) the null hypothesis. That means that we (found) evidence to support the alternative.
