Which calculation gives the width in inches from width in pixels and PPI?

Which calculation gives the width in inches from width in pixels and PPI?

• A. Width in inches times PPI gives width in pixels.
• B. Width in pixels divided by PPI gives the width in inches.
• C. PPI multiplied by height in pixels gives inches.
• D. Pixels per inch minus width in pixels.

Answer: (B)

Think of PPI as how many pixels fit into one inch. To get a width in inches from a width in pixels, divide the pixel width by the PPI. That’s because PPI tells you how many pixels there are per inch, so dividing by that density converts pixels into inches (pixels cancel, leaving inches). For example, 600 pixels wide at 300 PPI equals 600 ÷ 300 = 2 inches. The other ways don’t fit the same unit logic: multiplying pixels by PPI would mix units and isn’t a measure of physical size, while using height in pixels or subtracting numbers also doesn’t produce inches. The division is the correct way to turn a pixel measurement into inches.

Think of PPI as how many pixels fit into one inch. To get a width in inches from a width in pixels, divide the pixel width by the PPI. That’s because PPI tells you how many pixels there are per inch, so dividing by that density converts pixels into inches (pixels cancel, leaving inches). For example, 600 pixels wide at 300 PPI equals 600 ÷ 300 = 2 inches.

The other ways don’t fit the same unit logic: multiplying pixels by PPI would mix units and isn’t a measure of physical size, while using height in pixels or subtracting numbers also doesn’t produce inches. The division is the correct way to turn a pixel measurement into inches.