Answer:
Step-by-step explanation:
Hello!
The study variable is:
X: number of customers that recognize a new product out of 120.
There are two possible recordable outcomes for this variable, the customer can either "recognize the new product" or " don't recognize the new product". The number of trials is fixed, assuming that each customer is independent of the others and the probability of success is the same for all customers, p= 0.6, then we can say this variable has a binomial distribution.
The sample proportion obtained is:
p'= 54/120= 0.45
Considering that the sample size is large enough (n≥30) you can apply the Central Limit Theorem and approximate the distribution of the sample proportion to normal: p' ≈ N(p;
)
The other conditions for this approximation are also met: (n*p)≥5 and (n*q)≥5
The probability of getting the calculated sample proportion, or lower is:
P(X≤0.45)= P(Z≤
)= P(Z≤-3.35)= 0.000
This type of problem is for the sample proportion.
I hope this helps!
Let, speed of 1st bicyclist is x.
So, speed of 2nd bicyclist is x-3 .
We know, relative speed when two objects moves towards each other :
Now, distance travelled in 3 hours is (98-2) miles .
So,
Therefore, speed of bikes are 17.5 mph and 14.5 mph.
Hence, this is the required solution.
Time from October 5 to January 16
T=26+30+31+16=103 days
I=1870*0.11*103/365=58.05
P=2*(l+w)
p=2l+2w
2w=p - 2l
w= (p-2l)/2
Answer:
Part A: The population are the American adult citizens, excluding the ones from Alaska and Hawaii. The population is the people which the sample is trying to represent, as a hole.
The sample is a portion of this population, and in this case is represented by a randomly selected amount of people whose response to the interview has been selected.
Part B: The sample here has been selected in two steps. The first step is the one that we must pay attention to: the numbered list of one million responses from around the US (excluding Alaska and Hawaii). Because these responses were obtained by an online survey, the sample looks like a convenience sampling, as it depends on the availability and willingness from participants to take part of the study (is not compulsory for everyone, so not everyone is going to response, then there are people that is not going to be represented by). The second step is the random selection of a part of the previous responses. This last part will ensure that, the individuals that took part of the group that was interviewed, are well represented in the results.
Part C: As it was mentioned, there is a selection bias, because the information from the sample comes from a specific group of people that has certain features that may not represent all American adults citizens. For example, the opinion of those people who do not use internet, will not be considered (and they may be a large number of persons). This situations weaken the conclusions obtained in the study, as they are not representative of the hole population.
Step-by-step explanation:
