How long would it take for ball moving in a straight line to travel 246 meters?
(1) It takes the ball 2 seconds to make 1 rotation.
(2)The ball makes 7 rotations per meter.
The OA is C.
Why do I need statement (2) to solve this DS question? I don't know how to use statement(1). Experts, can you give me your help? Thanks.
How long would it take for ball moving in a straight line
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Hi VJesus12,
We're asked how long it would take for a ball moving in a straight line to travel 246 meters.
1) It takes the ball 2 seconds to make 1 rotation.
Fact 1 gives us some information about the 'speed' of the ball, but we don't know how much distance is traveled by 1 rotation.
Fact 1 is INSUFFICIENT.
2)The ball makes 7 rotations per meter.
Fact 2 tells us how much distance is traveled by 1 rotation (re: 1/7 meter) but does not tell us anything about the 'speed' of the ball.
Fact 2 is INSUFFICIENT.
Combined, we know the speed of the ball in rotations and seconds (14 seconds to travel 1 meter), so we CAN determine how long it would take to travel 246 meters. While we don't have to actually do the math, the equation would be:
246 meters = (1/14 meter per second)(X seconds)
Combined, SUFFICIENT.
Final Answer: C
GMAT assassins aren't born, they're made,
Rich
We're asked how long it would take for a ball moving in a straight line to travel 246 meters.
1) It takes the ball 2 seconds to make 1 rotation.
Fact 1 gives us some information about the 'speed' of the ball, but we don't know how much distance is traveled by 1 rotation.
Fact 1 is INSUFFICIENT.
2)The ball makes 7 rotations per meter.
Fact 2 tells us how much distance is traveled by 1 rotation (re: 1/7 meter) but does not tell us anything about the 'speed' of the ball.
Fact 2 is INSUFFICIENT.
Combined, we know the speed of the ball in rotations and seconds (14 seconds to travel 1 meter), so we CAN determine how long it would take to travel 246 meters. While we don't have to actually do the math, the equation would be:
246 meters = (1/14 meter per second)(X seconds)
Combined, SUFFICIENT.
Final Answer: C
GMAT assassins aren't born, they're made,
Rich