The total amount of profits of Brandeburgh Bicycle Company (BBC) must have increased dramatically over the last 5 years. After BBC developed a light and strong new material for its bicycles, total sales increased to twice what they were 5 years ago. Nevertheless, sales of certain types of bicycles, for which the new material is not used due to its high cost, have remained constant or, as is the case with bicycles for children, have decreased. Four years ago, sales of children’s bicycles constituted 30 percent of the total bicycle sales of BBC, and now they constitute barely 20 percent of all BBC’s sales.The conclusion of the argument is the following:
The total amount of profits of Brandeburgh Bicycle Company (BBC) must have increased dramatically over the last 5 years.The support for the conclusion is the following:
After BBC developed a light and strong new material for its bicycles, total sales increased to twice what they were 5 years ago.We are given some other information about BBC's sales as well, but the author appears to have decided that, whatever the mix of products sold has been, since BBC's ales have doubled, its profits must have increased dramatically.
Which of the following must be assumed in order for the assertion that the total amount of profits of BBC has increased dramatically over the last several years to be true?This is an Assumption question, and the correct answer will be the one such that it's necessary in order for the evidence to effectively support the conclusion.
(A)Increased sales always result in increased profits.The argument doesn't require this.
After all, the argument is about one company's results over one 5-year period. So, the argument works even if it's not true that, in the case of every company ever, increased sales results in increased profits.
Eliminate.
(B)BBC bicycles are not significantly more expensive than 5 years ago.Even if BBC bicycles are more expensive, the company could be more profitable. After all, the company could have increased profits by increasing prices.
So, this doesn't have to be true for the argument to work.
Eliminate.
(C)Over the last 5 years, total sales of BBC racing bicycles did not decrease by more than 70 percent.Even if sales of bikes in this product line decreased, sales overall doubled. So, even if this choice is not true, the evidence still indicates that profits increased.
Eliminate.
(D)Over the last 5 years, the average amount of profit gained by BBC per bicycle sale has decreased by less than 50 percent.This choice is interesting.
The only evidence we have that indicates that BBC is more profitable is that sales doubled.
So, if the the average amount of profit gained by BBC per bicycle sale has decreased by 50 percent or more, then the argument is wrecked.
After all, if revenue doubled but profit per unit sold decreased by 50 percent, then we have the following outcome:
Profit 5 years ago = Bikes × Profit per bike
Profit now = (2 × Bikes) × (1/2 × Profit per bike)
We see that, if the profit per bike decreased by half, then profits didn't grow at all. So, if profit per sale decreased by 50 percent or more, then, if BBC's sales doubled, BBC is no more profitable or is less profitable than it was 5 years ago.
So, for the argument to work, it must be the case that "Over the last 5 years, the average amount of profit gained by BBC per bicycle sale has decreased by less than 50 percent."
Keep.
(E)The proportion of bicycle market occupied by bicycles of BBC has not decreased over the last 5 years.The argument doesn't depend on this.
After all, regardless of BBC's market position, BBC itself could have become more profitable.
Eliminate.
Correct answer: D