Maths Olympiad Prep

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, 2004

Algebra Difficulty 3.0 AMC 10/12 Prove it Canada

Digital images consist of a very large number of equally spaced dots called pixels. The resolution of an image is the number of pixels/cm in each of the horizontal and vertical directions. Thus, an image with dimensions 1010 cm by 1515 cm and a resolution of 7575 pixels/cm has a total of (10×75)×(15×75)=843750(10\times75)\times(15\times75)=843\,750 pixels. If each of these dimensions was increased by n%n\% and the resolution was decreased by n%n\%, the image would have 345600345\,600 pixels. Determine the value of nn.

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