manik11 wrote:If a bicycle has two wheels of different sizes, at how many rotations per minute does the larger wheel rotate?
(1) The smaller wheel rotates at 3 meters per second.
(2) The larger wheel has a diameter twice as long as the smaller one.

OA : E

[email protected] wrote:Hi manik11,

This DS question can be solved with logic and/or TESTing VALUES.

We're told that the two wheels are DIFFERENT sizes. We're asked how many rotations per minute the LARGER wheel rotates.

1) The smaller wheel rotates at 3 meters per second.

This tells us NOTHING about the larger wheel.
Fact 1 is INSUFFICIENT.

2) The larger wheel has a diameter twice as long as the smaller one.

This gives us no 'measurable' information (re: the circumference of the wheel, the rate that it spins, etc.), so there's no way to answer the question.
Fact 2 is INSUFFICIENT.

Combined, we know the DISTANCE that the smaller wheel rotates through, but we don't know its size or the number of actual rotations that it rotates through per minute. Thus, knowing how the diameter of the larger wheel relates to that of the smaller wheel would lead to an unlimited number of answers to this question.
Combined, INSUFFICIENT.

Final Answer: E

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