In an attempt to understand the nation’s opinion on universal healthcare, investigators sponsored an advertisement at the end of a popular morning talk show in the US that asked viewers the following question: "Should everyone have healthcare? Visit our website at popularmorningshow and fill out the survey between 4pm and 6pm Pacific time and we’ll discuss the results on tomorrow’s show."

a. What population are the investigators are trying to sample, and do they obtain a representative sample from this sampling scheme?
b. Specifically, what type of sampling scheme has been used?
c. What type of sampling bias(s) may have occur? Explain.
d. What else could be a source of issue when it comes to this scenario? Explain.

a. The investigators want to get the opinion of the adult population about universal health care.

No, the target audience is not a representative sample of the population

b. Convenience sampling

c. Selection bias

d. The call to action (participation int he survey does not follow immediately), it is to take place between 4pm - 6pm

Step-by-step explanation:

a. For this type of survey (like any other), the best sampling technique to employ is random sampling. Random sampling is a sampling method in which every person has an equal chance of being selected. However, in this case, the investigators focused only on those with access to TV & specifically, those who watch this popular morning show on the day the survey is to be announced.

A representative sample refers to a smaller category of the popultion that gives an accurate depiction of the population. In this case, the target audience is not a representative sample of the population. It does not capture the opinion of those who live below the social status line (who have no access to the popular morning show).

b. Convenience sampling was used. In this sampling technique, data to be collected & worked with are those that are easy to get (in this case, those that watch the popular morning show). They do not reflect the true opinion of the population.

c. Selection bias is a sampling bias in which the data being worked with was gotten wrongly (usually the sampling technique does is not a true representation). As a result, the data obtained only reflects a sub-category of the target population rather than the entire population. In this case, the bias is that only a portion of the population watches the popular morning show and those who don't watch the show that day or who don't have access to the popular morning show are left.

d. Also, by the investigators projecting the time for the filling of the survey to be later in the day and not immediately (between 4pm - 6pm), they risk a significant number of the population forgetting to participate. This is because a call to action does not follow the popular morning show immediately. Not forgetting that the survey completely leaves out those without access to the popular morning show

2 Subway Tickets and 3 Express Bus Tickets

To solve this problem, you first need to write the following 2 equations.
6x + 4y = 24
3x + 7y = 27
Where x is the number of subway tickets and y is the number of bus tickets.

Now, you just have to solve the system of equations. You can use substitution, elimination or graphing. The easiest is graphing. There are online graphing calculators that will graph the points and you just need to find the point of intersection.