#21 - Thirty years ago, the percentage of their income that

[SherryZ]

Hi there, thank you very much for helping me! It truly means a great deal to me!

June 2001 LSAT, Sec 3 LR, #21:

Could you explain why A is WRONG and C is correct. Why C can justify the conclusion but A cannot?

Thank you!!

Sincerely,
Sherry

[Jacques Lamothe]

Hi Sherry,

The problem with (A) is that it makes a claim about the amount of food eaten per capita (which includes married persons), while the stimulus makes an argument based on the food purchasing behavior of singles. Hypothetically, food eaten per capita could be identical to its levels 30 years ago, but single persons could be eating half as much if married persons were eating enough to have kept the average constant. In that case, the observed 50% decrease in the amount that single persons spend on food would not be due to income rising faster than food prices. Alternatively, single people could have begun to buy much cheaper kinds of food in the last 30 years. In that case, food prices could be rising faster than income but single persons offset it by switching to a diet of the cheapest food they could find.

Answer choice (C) eliminates both of these possibilities. If (C) is true, than we know single persons are eating about the same amount of food (married persons no longer affect the average) and the same kinds of food (the answer explicitly says this). So even though answer choice (A) might help to justify the conclusion a bit, answer choice (C) helps to justify the conclusion much more because it avoids the above-mentioned problems of choice (A).

I hope that helps!

Jacques

[SherryZ]

Hi Jacques,

Thank you for your reply! Since my first language is not English, I misunderstood the concept of "Single Persons". I thought "Single" here means "Sole" rather than "Unmarried".

Could you tell me when "Single" means "Sole"??

Thanks a lot!

---Sherry

[Dave Killoran]

Hi Jacques,

Thank you for your reply! Since my first language is not English, I misunderstood the concept of "Single Persons". I thought "Single" here means "Sole" rather than "Unmarried".

Could you tell me when "Single" means "Sole"??

Thanks a lot!

---Sherry

Hi Sherry,

Do you mean in general? Because in those instances it will be based on context, and often preceded by "a," as in "Not a single person attended my party" "or "There was just a single person at the park today."

Thanks!

[Jerrymakehabit]

(D) is so tempting to me. If the non-food items' prices (Income minus food prices) rise faster than food prices, and food prices' percent drops, then income rise faster than food prices (conclusion). What is wrong with this logic? Can someone please help?

Thanks
Jerry

[Brook Miscoski]

Jerrymakehabit,

This is a strengthen ("most justify") question, so we have to support the conclusion. The conclusion is that incomes rose faster than the price of food. When I read this stimulus, my natural reaction is that people could just buy less food or crappier food, and the right choice, (C), addresses that by holding the quantity and quality of food constant.

(D) states that the prices of nonfood items have risen faster than the price of food. That doesn't tell me anything about how much food prices have risen compared to income.

Imagine:

1989 Bob makes $10,000 and spends $5,000 on food items.
2019 Bob makes an unknown amount of money and spends 25%, an unknown amount, on food items.
Bob is still single (awww).

Prove: The reason that Bob is spending a lower % of his income on food items is (basically) because he makes more money now.

(C) Bob is still buying the same quality and quantity of food--this helps.
(D) The price of nonfood items went up more than the price of food items--this does nothing to show that Bob is making more money. He could be buying fewer nonfood and fewer food items.

[pandapaws]

I'm still confused on why A is wrong. Doesn't it rule out the alternative explanation that it’s still possible that the reason single people spend less of their income on food today is because they’re eating less, thus strengthening the argument?

[Dana D]

Hey Panda,

First we want to keep in mind that we are always looking for the best answer, which here means the answer that most strengthens the argument. Answer Choice (A) is very general - the stimulus is talking about single people specifically, while this answer talks about food eaten per capita, thus opening up the population of people we're talking about far beyond just single people.

Furthermore, even if answer choice (A) was true, we need to ask if it helps justify the author's conclusion, which is that incomes have risen at a greater rate than the price of food. Answer choice (A) might help slightly, by saying that the amount eaten has stayed the same, but answer choice (C) strengthens it even more by specifically addressing single people - so we're looking at the same population in both cases - and by eliminating another factor that could skew the results by saying single people eat the same type of food as well. So, with answer choice (C), the comparison between present day and 30 years ago is consistent in terms of both the quantity and type of food, which strengthens the author's ability to deduce that incomes must have risen at a greater rate than the price of food.

Hope that helps!