imhimanshu wrote:
Last August the XT chain of gasoline stations had a temporary sales promotion in effect. In the promotion, any customer who made a purchase of ten or more gallons of gasoline was entitled to a free car wash. For the month of August, XT experienced a ten percent increase in gasoline sales as compared to sales in August the previous year, so evidently the promotion was successful as a means of boosting sales.
In evaluating the argument, it would be most helpful to answer which of the following?
(A) In the areas in which XT’s gasoline stations operate, how did total combined gasoline sales for all gasoline stations last August compare with sales for the previous August?
(C) Were there any customers who bought ten or more gallons at an XT gasoline station during the promotion who would have bought gasoline at the same station in lower quantities, but more frequently, if the promotion had not been in effect?
Hi experts
avigutman IanStewartI ran into this question in my practice exam, spent about three minutes but still got it incorrectly. I've checked all the previous posts in this thread, but still have a few doubts for the option (C). Could you share some of your thoughts when you have time?
To be honest, I have no much confidence in the evaluation-type questions, as I feel that the workload is twice that of a strengthen/weaken type question, and can eat up my time easily. Some tutors have shared their approach online. They said that since almost all answer choices in the evaluation-type question begin with "whether" or are "yes or no" questions, test takers can change the option, an interrogative sentence, into an affirmative sentence by assuming the answer to the question is "yes," and check whether the new sentence strengthens or weakens the argument. If it can, there is no need to check another version and the option would be the correct answer.
I am not to criticize this approach (I think it is invented to help people save time), but as you may imagine, I was kind of lost when I saw the option (A), which is a question with "how" and cannot be really converted into an affirmative sentence. Moreover, I misinterpreted (A) as talking about the
combined gasoline sales for all XT's gasoline stations, rather than
for all gasoline stations (XT and non XT), and thus I turned away.
Instead, I chose (C), as I felt that it could somehow answer the question "Did the promotion help boost the sales?" My thought was that because these customers who bought ten or more gallons last August would have bought less gas (each time) but bought gas more frequently if there had been no free car wash, it is possible that the combined amount of gas these customers bought last August were the same from a year earlier. Then, we can infer that the promotion is not an effective means, and there must be another reason for the 10 percent increase in sales.
Quote:
(C) Were there any customers who bought ten or more gallons at an XT gasoline station during the promotion who would have bought gasoline at the same station in lower quantities, but more frequently, if the promotion had not been in effect?
Is my original train of thoughts wrong because I did not catch the very word "
any" in the option (C)? The option (C) does not talk about the customers in general, but talks specifically whether there was at least one such a customer.
The "yes" answer to (C): Yes, there is at least one such a customer. This customer bought ten or more gallons at an XT gasoline station during the promotion, and he or she would have bought gasoline at the same station in lower quantities, but more frequently, if there had been no free car wash. =>Okay, maybe this customer in fact bought the same amount of gas as he or she did a year earlier. But how about other customers? We do not know whether they bought more gas because of free car wash. Hence, we cannot strengthen or weaken the argument that the promotion helped boost the sales.
The "no" answer to (C): No, there was not such customer. => The "no" version just tells us that no one would have bought less gas each time but bought more frequently if there had been no free car wash. And we cannot assume other things. How much gas did these customers buy? We have no idea. Without the promotion, they might have bought less gas in total (for example, 8 gallons once) or they bought the same amount of gas (for example, 10 gallons once). Hence, we are not clear whether the customers bought more gas last August because of the promotion. We cannot strengthen or weaken the argument.
(My thought was similar to the following, but now I see that we cannot ignore the word "ANY" and assume about the customers lightly.)
Moussaillon wrote:
Let's say I apply the variance test to C:
1) Yes - there were customers who bought 10+ gallons who would have otherwise bought gasoline in lower quantities but more frequently. This means customers would have bought that amount of gasoline regardless of promotion - Weakens the argument
2) No - no customers who bought 10+ gallons would have otherwise bought gasoline in lower quantities but more frequently. This means that the customers who bought 10+ gallons wouldn't have bought that much gasoline in the first place - Strengthens the argument
Based on that interpretation, C sounds like a good choice
Besides, I hope to confirm the logic about the correct option (A).
I think that even if we know the growth rate of the combined gas sales of all gasoline stations in the areas where XT operates, we cannot be 100 percent certain whether the promotions is effective (unless the question stimulus tells us all other things being equal, but they never do so). For example, even if the combined sales grew 5 percent annually, less than XT's sales did, there could be an explanation other than free car wash for the higher growth in XT's sales, such as extended service hour. Even if the combined sales grew 10 percent, the same as XT's sales did, it does not necessarily mean that the promotion was not effective--maybe all gasoline companies launched new campaign last August (as all cosmetics companies tend to do something in November), and if XT had not offered the free car wash, it would have seen a revenue drop.
But the point is that we do not need to be 100 percent certain whether the promotion is effective, do we? If evaluation is really just a combination of strengthen and weaken type question, the information in the correct option does not need to prove or disprove the argument, right?
Thank you so much!
Your explanations would help me know more clearly about my task in the evaluation type questions.
Thank you for helping me learn.