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"If you know how to calculate image size and PPI when printing, you'll be sure that your printed photos are crisp and vibrant. Learn about how to calculate image size and PPI when printing in this article."^^<http://www.w3.org/2001/XMLSchema#string>
<http://electronics.howstuffworks.com/cameras-photography/digital/how-to-calculate-image-size-and-ppi-when-printing.htm>