Mountain biking on trails is soaring in popularity in the United State

Question

Mountain biking on trails is soaring in popularity in the United States. The number of mountain bikes sold in the United States has increased 133 percent over the past four years. In addition, bike stores in the United States last year reported that mountain bikes accounted for more than 65 percent of their total sales, far more than in previous years, even though sales of other bikes have been strong.

The conclusion above is based on which of the following assumptions?

A. Mountain biking on trails is getting popular.
B. stores are selling more mountain bikes and mountain bikes are a greater proportion of their overall bike sales.
C. The people who are buying bikes must be using them on trails.
D. Most of the people who are driving the increase in mountain bike sales are involved in trail cycling.
E. People who buy mountain bikes tend to use them in urban or suburban settings, rather than on trails.

nishantd88 · Accepted Answer

Mountain biking on trails is soaring in popularity in the United States. The number of mountain bikes sold in the United States has increased 133 percent over the past four years. In addition, bike stores in the United States last year reported that mountain bikes accounted for more than 65 percent of their total sales, far more than in previous years, even though sales of other bikes have been strong.

The conclusion is Mountain biking on trails is soaring in popularity in the United States.
Quite a few assumptions are there.
1. The bikes that are sold are used in the US and not exported.
2. Those who are buying the bikes are using them on trails.
3. The increase in sales is driven by more people getting interested in mountain biking rather than existing bikers replacing their old bikes.

Let's see the options now.

The conclusion above is based on which of the following assumptions?
A. Mountain biking on trails is getting popular.  Just restates the conclusion. 
B. stores are selling more mountain bikes and mountain bikes are a greater proportion of their overall bike sales.  Just restates a premise mentioned in the passage. 
C. The people who are buying bikes must be using them on trails.  Correct option. 
D. Most of the people who are driving the increase in mountain bike sales are involved in trail cycling.  Might seem to be a good option. But consider other possibilities. For example, the people maybe buying mountain bikes, but using other bikes they own on the trails.  
E. People who buy mountain bikes tend to use them in urban or suburban settings, rather than on trails.  GOes against the conclusion. It implies the increase is sales is because mountain bikes are used in settings other than trails.

samparnatripathy · Answer

Will vote for D.

If we negate this statement (most people who are driving this increase in mountain bike sales are NOT involved in trail cycling), it invalidates the conclusion.

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bapism07 · Answer

C

A. Mountain biking on trails is getting popular. - It is the conclusion
B. stores are selling more mountain bikes and mountain bikes are a greater proportion of their overall bike sales. - It is not what is being the main point. It is the effect. 
C. The people who are buying bikes must be using them on trails. - By applying the negation technique, we will get nil motivation to buy the bikes. eg it hurts the most and hence it is the correct answer. 
D. Most of the people who are driving the increase in mountain bike sales are involved in trail cycling. - New information./ Shell answer: driving on trail and trail cycling are different. 
E. People who buy mountain bikes tend to use them in urban or suburban settings, rather than on trails. - New information.

chesstitans · Answer

D is a strengthener, while C is an assumption.

iamapoorva · Answer

I was confused between C and D. Marked D because C mentions about bikes, while I thought it should be mountain bikes -

The people who are buying     bikes must be using them on trails

chesstitans · Answer

the key word here is "Mountain biking  on trails "-> C fills the gap between mountain bikes and trails. -> C is the assumption.
The premise only supports the surge in sales of mountain bikes. The missing link here is "bikes for trails"

adv95 · Answer

i agree driving on trail and trail cycling are different. driving can include 4x4 atvs etc. but option is saying trail cycling which = mountain biking i think

NAIDHRUV · Answer

I believe, Option D is correct answer.
D. Most of the people who are driving the increase in mountain bike sales are involved in trail cycling.

This connects the evidence (sales) to the conclusion (trail biking popularity).

Negation:

Most of the people driving the increase in mountain bike sales are not involved in trail cycling.

If that were true, then the increase in mountain-bike sales would no longer support the claim that trail biking is becoming popular.

The argument collapses.

Whereas Option C is too broad or Strong,
C. The people who are buying bikes must be using them on trails.

Too strong because it says all people buying bikes must use them on trails.

Negation:

People buying bikes need not be using them on trails.

The argument could still survive if many mountain-bike buyers use trails.

Please explain why option C is correct why not option D

egmat · Answer

Hi NAIDHRUV,

The whole thing turns on how you negated each choice, so let's redo that carefully, because the negation of  C  actually  does  collapse the argument.

Fixing the negation of C.  C says  "The people who are buying bikes must be using them on trails."  Its real negation is  "The people buying these bikes are NOT using them on trails."  If buyers aren't riding on trails at all, then a  133%  jump in sales tells us nothing about trail biking - the surge could be exports, collectors, city commuters, anything. The bridge from  sales  to  trail popularity  is gone. So C's negation destroys the argument, which is exactly what makes C the necessary assumption. (You negated it too softly - "need not be using them on trails" isn't the opposite; it's a watered-down version.)

Why D is not necessary.  Look at what the conclusion actually needs: trail biking is  soaring . Now negate D properly:  "Most of the people driving the increase are NOT involved in trail cycling."  Notice "most" means  more than half . Even if only, say,  40%  of the new buyers ride trails, that's still a big rise in trail riders on top of a  133%  sales jump - trail biking can still be soaring. So the conclusion  survives  D's negation. An assumption the argument can live without is  not  a required assumption; that's why D is at best a strengthener, not the gap-filler.

On "C is too strong."  In an assumption question, the strong-sounding link is often exactly what you want, because the assumption is the plank the conclusion  stands on . The test isn't "does it sound strong?" - it's "does removing it break the argument?" C breaks it; D doesn't.

Quick habit to lock in: always negate to the true opposite, then ask  does the conclusion still hold?  Only the choice whose negation kills the conclusion is the assumption.

Answer: C

Mountain biking on trails is soaring in popularity in the United State

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Mountain biking on trails is soaring in popularity in the United State

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