This question has a great Number Property 'shortcut' built into it; when combined with the answer choices, you can avoid almost all of the 'math' in this question.
We're told that the dimensions of a rectangular room are 10 meters by 6 meters by 4 meters. We're asked for the volume of the room in cubic CENTIMETERS? (1 meter=100 centimeters).
Converting the dimensions from meters to centimeters is pretty straight-forward - we just have to multiply each number by 100:
10 meters by 6 meters by 4 meters becomes...
1000 cm by 600 cm by 400 cm
Notice that these three numbers include 7 zeroes. When we multiply them together, the correct answer MUST have at AT LEAST 7 zeroes. Looking at the answer choices, there's only one answer that fits:
GMAT assassins aren't born, they're made,
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