Vacuum cleaner salesperson: To prove that this Super XL vacuum cleaner is better than your old vacuum cleaner, I ran your old vacuum once over this dirty carpet. Then I ran the Super XL over the same area. All that dirt that the Super XL picked up is dirt your old vacuum left behind, proving the Super XL is the better vacuum.

Summarize Argument

The salesperson concludes that the Super XL is the better vacuum because it picked up dirt that the old vacuum missed after both were used on the same area of carpet. The Super XL was used second.

Identify and Describe Flaw

The salesperson's argument is vulnerable to criticism because the vacuums weren't tested under the same conditions. Just because the Super XL picked up some dirt that the old vacuum missed doesn't necessarily suggest that the Super XL is better. In fact, the Super XL might have missed just as much dirt if it had been used first. The salesperson should have tested both vacuums individually to compare how much dirt they each collected on their first pass over equally dirty areas of carpet.

A
ignores the possibility that dirt remained in the carpet even after the Super XL had been used in the test

The salesperson never assumes that the Super XL picked up all the dirt in the carpet. Presumably at least a little bit of dirt remained in the carpet after the Super XL was used, but this doesn't change the fact that it picked up dirt that the old vacuum left behind.

B
takes for granted that the Super XL will still perform better than the old vacuum cleaner when it is the same age as the old vacuum cleaner

The salesperson argues that the Super XL is the better vacuum right now. He never assumes that it will still perform better in 10 years.

C
takes for granted that because the Super XL outperforms one vacuum cleaner it is the best vacuum cleaner available

The salesperson never claimed that the Super XL is the best vacuum cleaner available, just that it’s better than the old vacuum.

D
ignores the possibility that the amount of dirt removed in the test by the old vacuum cleaner is greater than the amount of dirt removed by the Super XL

The salesperson’s argument isn’t about which vacuum picked up the greater amount of dirt. He never actually assumes that the Super XL picked up more dirt. Instead, he argues that the Super XL is better because it picked up dirt that the old vacuum left behind.

E
ignores the possibility that if the Super XL had been used first it would have left behind just as much dirt as did the old vacuum cleaner

The salesperson didn’t test the vacuums under the same conditions. He argues that the Super XL is better because it picked up dirt that the old vacuum missed on its first pass. But it’s possible that the Super XL might’ve left behind just as much dirt if it had been tested first.


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Manager: This company’s supply chain will develop significant weaknesses unless we make changes to our vendor contracts now. Some will argue that this problem is so far in the future that there is no need to address it today. But that is an irresponsible approach. Just imagine if a financial planner offered the same counsel to a 30-year-old client: “Don’t worry, Jane, retirement is 35 years away; you don’t need to save anything now.” That planner would be guilty of gross malpractice.

Summarize Argument: Counter-Position
The manager claims that it would be irresponsible for the company to wait to address future supply chain issues. To support this claim, the manager uses an analogy, noting that if a financial planner encouraged a client to postpone retirement planning simply because retirement is in the future, the planner would be engaging in malpractice.

Identify Conclusion
The conclusion is the manager’s claim that it would be irresponsible for the company to wait to address future supply chain issues: “that is an irresponsible approach.”

A
Some people argue that the supply-chain problem is so far in the future that there is no need to address it now.
This is not the conclusion, it is context about the stance the manager is arguing against.
B
It would be irresponsible to postpone changes to the vendor contracts just because the supply chain will not develop weaknesses for a long time.
This rephrases the conclusion.
C
If no changes are made to the vendor contracts, the supply chain will eventually develop significant weaknesses.
This is a premise, not the overall conclusion. By stating that the company’s supply chain will develop significant weaknesses if changes are not made immediately, the manager supports the conclusion that to postpone the necessary changes would be irresponsible.
D
In planning to meet its future obligations, a company should follow the same practices that are appropriate for an individual who is planning for retirement.
This is not the manager’s conclusion. The manager uses the retirement example as an analogy to illustrate how postponing action can be detrimental, but does not conclude that the company should follow the same practices as an individual who is planning for retirement.
E
Financial planners should advise their clients to save money for retirement only if retirement is many years away.
The manager does not make this claim.

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Worldwide, more books were sold last year than in any previous year. In particular, there were more cookbooks sold. For the first time ever, most of the cookbooks sold were not intended for beginners. Indeed, more cookbooks than ever were purchased by professional cooks. However, one of the few books available on every continent is a cookbook written for beginners, entitled Problem-Free Cooking.

Summary

Last year, more books were sold worldwide than ever before, especially cookbooks. For the first time ever, most of these cookbooks were not intended for beginners. In fact, more cookbooks than ever were bought by professional cooks. However, one cookbook for beginners, Problem-Free Cooking, is one of the few books available on every continent.

Strongly Supported Conclusions

There could be an increasing demand for professional-level cookbooks.

There were more cookbooks sold last year that were not intended for beginners than in any other year.

There are few cookbooks that are available on every continent.

A
Last year there were more cookbooks sold that were not intended for beginners than in any previous year.

Strongly supported. More cookbooks were sold last year and, for the first time ever, the majority of these cookbooks were not intended for beginners. Thus, there were more cookbooks sold last year that were not intended for beginners than in any previous year.

B
The best-selling cookbook last year was a cookbook that was intended for beginners.

Unsupported. Problem-Free Cooking is intended for beginners and is available on every continent, but we do not know that it was the best-selling cookbook last year. We also do not know whether any other cookbook intended for beginners was the best-selling cookbook last year.

C
Sales of cookbooks intended for beginners were lower last year than in previous years.

Unsupported. Sales of cookbooks not intended for beginners surpassed the sales of cookbooks intended for beginners. But that does not mean that the sales of cookbooks intended for beginners were lower last year than in previous years.

D
Most of the cookbooks purchased last year that were not intended for beginners were purchased by professional cooks.

Unsupported. We know that professional cooks purchased more cookbooks than ever. But we do not know whether most of the cookbooks that were not intended for beginners were purchased by professional cooks. Perhaps beginners still purchased lots of non-beginner books.

E
Problem-Free Cooking sold more copies last year than did any cookbook written for professional cooks.

Unsupported. Problem-Free Cooking is available on every continent, but we do not know how many copies it sold or whether it sold more copies last year than any cookbook written for professional cooks.


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