For this case, the first thing we are going to do is write the generic equation of motion for the vertical axis.
We have then:
Where,
For the first body:
For the second body:
By the time both bodies have the same height we have:
Rewriting we have:
Clearing time:
Answer:
it takes 18.31s for the two window washers to reach the same height
Answer:
0.335
Step-by-step explanation:
1. There is a 30 percent chance of a flight being delayed because of icy weather ,then the probability of being delayed is 0.3 and of being not delayed is 0.7.
2. If a flight is delayed because of icy weather, there is a 10 percent chance the flight will also be delayed because of a mechanical problem, then the probability of being delayed is 0.1 and the probabilty of not being delayed is 0.9.
3. If a flight is not delayed because of icy weather, there is a 5 percent chance that it will be delayed because of a mechanical problem (MP), then the probability of being delayed is 0.05 and the probabilty of not being delayed is 0.95. (See attached probability tree)
Delayed of icy weather - 0.3
Delayed of MP when weather is not icy - 0.7·0.05=0.035
Now, if one flight is selected at random from the airport in January, the probability that the flight selected will have at least one of the two types of delays is
0.3+0.035=0.335
Answer:
For this case we have the following info related to the time to prepare a return
And we select a sample size =49>30 and we are interested in determine the standard deviation for the sample mean. From the central limit theorem we know that the distribution for the sample mean is given by:
And the standard deviation would be:
And the best answer would be
b. 2 minutes
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The central limit theorem states that "if we have a population with mean μ and standard deviation σ and take sufficiently large random samples from the population with replacement, then the distribution of the sample means will be approximately normally distributed. This will hold true regardless of whether the source population is normal or skewed, provided the sample size is sufficiently large".
Solution to the problem
For this case we have the following info related to the time to prepare a return
And we select a sample size =49>30 and we are interested in determine the standard deviation for the sample mean. From the central limit theorem we know that the distribution for the sample mean is given by:
And the standard deviation would be:
And the best answer would be
b. 2 minutes